Terms of Use

At Grinfer B.V. ( “Grinfer”, “we”, “us” “our”), our mission is to spread knowledge and experience to help others improve their lives and acquire new knowledge. We give anyone an opportunity to create and share educational courses and masterclasses (authors), provide audio and/or video consultations (instructors)  and enroll in educational courses to learn or take consultations (learner).

Please read carefully and fully the below-written rules. These Terms apply to all your activities on the Grinfer website - www.grinfer.com ("Site"), and other related services (“Services”).

Acceptance of Terms

  1. ‍By registering for and/or using the Services in any manner, including but not limited to visiting or browsing the Site, you agree to these Terms of Service (including, for clarity, the Privacy Policy) and all other operating rules, policies and procedures that may be published from time to time on the Site by us, each of which is incorporated by reference and each of which may be updated from time to time without notice to you.

  2. Certain of the Services may be subject to additional terms and conditions specified by us from time to time; your use of such Services is subject to those additional terms and conditions, which are incorporated into these Terms of Service by this reference.

  3. These Terms of Service apply to all users of the Services, including, without limitation, users who are contributors of content, information, and other materials or services, registered or otherwise.

  4. Arbitration notice and and class action waiver: except for certain types of disputes described in the arbitration section below, you agree that disputes between you and Grinfer will be resolved by binding, individual arbitration and you waive your right to participate in a class action lawsuit or class-wide arbitration.


You represent and warrant that you are at least 18*  years of age. If you are younger than the required age, you may not set up an account, but we encourage you to invite a parent or guardian to open an account and help you enroll in courses that are appropriate for you. If we discover that you have created an account and you are younger than the required age for consent to use online services (for example, 13 in the US), we will terminate your account. You may be requested to verify your identity before you are authorized to submit a course for publication.

If you think that we may have any information from people aged under 18* years old or about him, contact Grinfer, located at: Kamer241, Keizersgracht 241, 1016 EA Amsterdam, The Netherlands or support@grinfer.com.

We may, in our sole discretion, refuse to offer the Services to any person or entity and change its eligibility criteria at any time. You are solely responsible for ensuring that these Terms of Service are in compliance with all laws, rules, and regulations applicable to you and the right to access the Services is revoked where these Terms of Service or use of the Services is prohibited or to the extent offering, sale or provision of the Services conflicts with any applicable law, rule or regulation. Further, the Services are offered only for your use, and not for the use or benefit of any third party. If you are registering with Grinfer on behalf of an entity or a third party, you represent and warrant that you have full authority to bind that entity to these Terms of Service.

Registration and Accounts

You need an account for most activities on our platform, including to purchase and enroll in a course or to submit a course for publication, or offer consultations. When setting up and maintaining your account, you must provide and continue to provide accurate and complete information, including a valid email address. You are solely responsible for the activity that occurs on your Account, and for keeping your Account password secure, including any harm or damage (to us or anyone else) caused by someone using your account without your permission. You must notify us immediately upon learning that someone else may be using your account without your permission (or if you suspect any other breach of security) by contacting our Support Team support@grinfer.com, and If you decide to delete your Account, you must contact our Support Team.

Rules of Conduct

1‍. As a condition of use, you promise not to use the Services for any purpose that is prohibited by these Terms of Service. You are responsible for all of your activity, and all activity connected to your Account in connection with the Services (including without limitation your communications and collection of data from other users of the Services).

2. You shall not (and shall not permit any third party to) either (1) take any action or (2) upload, download, post, submit or otherwise distribute or facilitate distribution of any Content, including without limitation User Content, on or through the Services that:

a. ‍infringes any patent, trademark, trade secret, copyright, right of publicity or other rights of any other person or entity, or violates any law, rule, or regulation (whether domestic, foreign, or international) or contractual duty;

b. violates these Terms of Use;

c‍. is unlawful, threatening, abusive, harassing, defamatory, libelous, deceptive, fraudulent, invasive of another's privacy, tortious, obscene, vulgar, pornographic, offensive, profane, contains or depicts nudity, contains or depicts sexual activity, or is otherwise inappropriate as determined by us in our sole discretion;

d. you know is false, misleading, untruthful or inaccurate;

e. contains software viruses or any other computer codes, files, or programs that are designed or intended to disrupt, damage, limit or interfere with the proper function of any software, hardware, or telecommunications equipment or to damage or obtain unauthorized access to any system, data, password or other information of ours or of any third party;‍

f. constitutes unauthorized or unsolicited advertising, junk or bulk e-mail (“spamming”);

g. impersonates any person or entity, including any of our employees or representatives;

h. includes anyone’s identification documents or sensitive financial information.

i. religious propaganda is prohibited, including incitement to religious hatred and enmity, insulting the religious feelings of believers, and the believers themselves. It's not allowed to mention religious organizations or movements that are prohibited by law in any country in the content you are publishing on Grinfer.

3. You shall not: 

a. take any action that imposes or may impose (as determined by us in our sole discretion) an unreasonable or disproportionately large load on our (or our third-party providers’) infrastructure; 

b. interfere or attempt to interfere with the proper working of the Services or any activities conducted on the Services; 

c. bypass, circumvent or attempt to bypass or circumvent any measures we may use to prevent or restrict access to the Services (or other accounts, computer systems or networks connected to the Services); 

d. run any form of auto-responder or “spam” on the Services; 

e. use manual or automated software, devices, or other processes to “crawl” or “spider” any page of the Site; 

f. harvest or scrape any Content from the Services;

g. otherwise take any action in violation of our guidelines and policies.

4‍. You shall not (directly or indirectly): 

a. decipher, decompile, disassemble, reverse engineer or otherwise attempt to derive any source code or underlying ideas or algorithms of any part of the Services (including without limitation any application), except to the limited extent applicable laws specifically prohibit such restriction, 

b. modify, translate, or otherwise create derivative works of any part of the Services,

c. copy, rent, lease, distribute, or otherwise transfer any of the rights that you receive hereunder. You shall abide by all applicable local, state, national and international laws, and regulations.

5. We also reserve the right to access, read, preserve, and disclose any information as we reasonably believe is necessary to:

a. satisfy any applicable law, regulation, legal process or governmental request, 

b. enforce these Terms of Use, including investigation of potential violations hereof, 

c. detect, prevent, or otherwise address fraud, security or technical issues, 

d. respond to user support requests,

e. protect the rights, property or safety of us, our users and the public.


1. For conducting audio and video consultations, Grinfer uses its own platform; the data transmitted during your audio and video consultations will not be transferred to third parties.

2. The learner can plan the duration of the consultation before sending the request. To plan the duration of the call, the learner can use time slots of fixed duration with the minimum of 30 minutes.
When the learner sends a request for a consultation of a minimum length (which is 30 minutes), they should note that this period of time includes 5 minutes for the teacher to prepare for the consultation and 25 minutes of the consultation itself. Thus, the instructor must conduct a consultation lasting at least 25 minutes.
If the learner sends a request for a consultation lasting 1 hour or more, then this period of time includes 10 minutes for the instructor to prepare for the consultation. Thus, the instructor must conduct a consultation equal to the planned duration minus 10 minutes for necessary preparation. If the consultation lasts longer than 1 hour, the instructor has 10 minutes for necessary preparation regardless of the duration of the session. 

3. The learner must send a request for consultation and make an advance payment before the consultation, but not earlier than 85 calendar days before it.

4. When sending a request, the learner has to make a 100% prepayment for the call. This amount of money will have a pending status in the learner’s account until the instructor confirms or declines the request.

5. The learner’s consultation request will be processed no later than 72 hours after sending.

  • If the instructor confirms a request, the pending transaction will be debited from the learner’s account. Payment is considered finalized when the money is transferred to Grinfer or a third party who charges a fee on our behalf (for example: PayPal, Stripe etc).

  • If the instructor declines a request, the learner will get the full refund for the consultation. The pending transaction in the learner’s account will be released. 

  • If the instructor does not take action (confirm or decline a request within 3 days from the receipt of the booking request), the consultation will be canceled automatically and the learner will get the full refund for this booking.  

6. The learner has the right to cancel the consultation. If the learner cancels the pending request before it is confirmed by the instructor, the learner will receive a full refund for this booking.

7. If the learner cancels the consultation request after it has been confirmed by the instructor and more than 24 hours prior to the start of the consultation, the learner will get the refund minus the processing fee of 4% of the total amount paid for the consultation.

If the learner cancels the request for consultation less than 24 hours prior to the start of the consultation and after it has been confirmed by the instructor, the learner will not get a refund for this consultation.

8. If the already approved consultation has been canceled by the instructor, the learner will receive a full refund for the consultation. The instructor has the right to cancel the confirmed consultation at any time before the scheduled start of the consultation. In this case, the instructor will be charged 4% processing fee of the total payment made by the learner for this consultation.

9. We will notify both learners and instructors about any status changes via email and notifications on Grinfer. 

10. The instructor has the right to end the consultation at the scheduled time.

If the learner did not show up at the consultation confirmed by the instructor, the learner will not get the refund for the consultation. 

If the learner joins the consultation with a delay of 15 minutes or more, the instructor has the right to refuse to conduct a consultation. In this case, the learner will not get a refund for this consultation.

If the learner joins the consultation with a delay and the instructor conducts a consultation, the learner is not entitled to demand a refund for the consultation time that was missed due to his absence.

11. If the instructor did not show up at the consultation, the learner has the right to request a full refund for the consultation.

12. If the instructor joins the consultation with a significant delay (more than 5 minutes), the learner is entitled to request a full or partial refund. The amount of the refund is calculated at Grinfer’s discretion. It can be a full or partial refund depending on the time lost due to the instructor’s absence.

13. In case of other disputes not described above, Grinfer has the right to make decisions at its own discretion.

14. In case of a dispute, both learner and instructor can contact us at support@grinfer.com. A request should be sent within 24 hours after the end of the consultation, otherwise the consultation is considered to be successfully completed and claims will not be accepted. The request will be processed in time and in accordance with the rules established by our Terms of Use, Author’s Agreement, etc.
To resolve a dispute, Grinfer has the right to request additional information both from the learner and instructor.

Minimum Technical Requirements for consultations

  1. Consultation functionality is available for desktop and laptop users only.

  2. To be able to use consultations on the Grinfer users should meet following minimum technical requirements:
    2.1 Minimum hardware requirements:

  • Processor: 1.0 GHz multi-core;

  • Memory: 2 GB or above;

  • Monitor: 13" HD (1280 x 720) or above;

  • Presence of a microphone;

  • Presence of a webcam.

2.2 Minimum software requirements:

  • Operating system: Windows 7/8/8.1/10, Mac OS X 10.11 and newer;

  • Browser: Google Chrome/ Safari of the latest stable version.

2.3 Minimum internet connection requirements:

  • the stable internet connection from 2 Mbps.

  1. Grinfer is not responsible for the inadequate quality of the consultation services in case if:

  • user`s hardware is not meeting the minimum hardware requirements listed in paragraph 2.1;

  • a user does not have any of the necessary software;

  • a user experiences technical problems with an Internet connection.


The Learner can purchase unlimited access to online courses and all premium stories on Grinfer (and articles, as well as its future updates) by Subscription (valid only for those courses and articles that are created by Instructors (Authors) who have agreed to give access on a Subscription basis).

Subscription content includes all existing and future courses of the Instructors (Authors) (together with updates) published on Grinfer, as well as paid articles in Grinfer’s blog (existing and future ones with updates). Subscription means that the Learner can purchase access to the available content of Subscription for a certain period of time, we offer 2 types of subscription plans for using our Services:
1 month
1 year
All plans come with a 3-day free trial, after this period, the amount for the Subscription will be automatically debited from your account.

After the Learner cancels the Subscription, access to online courses and all premium stories on Grinfer (and articles, as well as its future updates), which were available by this Subscription, is terminated immediately at the end of the paid period.

Subscription renewal rules

If you purchase any subscription plan to a Service with an auto-renewal feature (“Recurring Subscription”), you authorize Grinfer to maintain your account information and charge that account automatically upon the renewal of the Service you choose without any additional action from your side. In case, Grinfer cannot charge your account as authorized by you when you purchased a Recurring Subscription, Grinfer, may, in its sole discretion, bill you for the Service purchased by you and suspend your access to the Service until payment is received.

Grinfer may change the prices and/or duration periods (including duration of the free trials) for Recurring Subscriptions from time to time and will notify you about any price changes in advance and, if applicable, how you can accept those changes. Price changes for Recurring Subscriptions will take effect at the start of the next subscription period following the date of the price change. If you continue to use your Recurring Subscription after the price change takes effect that means you accept those price changes. If you do not want to accept price changes, you can cancel your Recurring Subscription before the price change takes effect. Please, read any notification of price changes carefully.

Payments are final and nonrefundable. Please note there are no refunds or credits for partially used periods. You may cancel a Recurring Subscription at any time, but if you cancel your subscription before the end of the current subscription period, we will not refund any subscription fees already paid to us. If you choose to cancel your subscription, you will still have access to the service till the end of your current subscription period. Providing a refund or a discount, or any other consideration to some or all of our users or refusing to do so stays at our sole discretion. 

If you purchase any Service through a mobile app purchase or third-party marketplace (e.g., through the Apple App Store or Google Play Store), the refund policy applicable to that third-party marketplace will apply, unless otherwise explicitly stated by Grinfer. Except as otherwise explicitly stated by Grinfer, the third-party marketplace will be solely responsible for making refunds under its refund policy, and Grinfer will have no refund obligations. Grinfer disclaims any responsibility or liability related to any third-party marketplace's refund policy or the third party's compliance or noncompliance with such policy.

If you subscribed via iTunes on your Apple mobile device, you can cancel by going to your Account Settings in the App Store. You can find Subscriptions in the Settings app on your device under iTunes & App Store, and then select your Apple ID.

If you subscribed via the Google Play Store on your Android mobile device, you can cancel by opening the Google Play Store and selecting Menu Subscription. You can select the subscription you want to cancel or update and then follow the onscreen instructions.

If you subscribed on our website, you can cancel by contacting Support at support@grinfer.com, or by going to Settings in your account and canceling your subscription there.

Exclusions from subscriptions

Please note that due to pre-existing agreements with some of our instructors, a small number of instructors and courses are excluded from the Subscription and can only be purchased separately. Review the exclusions list below:

  • Rob Percival’s Codestars

  • How Hackers Find SQL Injections in Minutes with Sqlmap

  • Web Hacking Secrets: How to Hack Legally and Earn Thousands of Dollars at HackerOne

  • Web Hacker’s Toolbox: Tools Used by Successful Hackers

  • Web Hacking Expert: Full-Stack Exploitation Mastery

For users, who don’t want to subscribe, there is an option of buying some courses separately. If you purchase an individual course, you proceed with a one-time payment and get lifetime access to this course.

Note for users who previously purchased a web subscription to a certain instructor:
As we are moving to an all-access pass, you’ll automatically get access to all courses on Grinfer available by subscription without any changes in your recurring payment.

Subscription payments

The amount of payment for the Subscription is charged as a one-time payment for the entire selected period of the Subscription.

Grinfer for Business

Administrator account (referred to as “Admin account” thereafter) is a digital account created under the Grinfer for Business Subscription plan on behalf of a legal entity which is used by the legal entity for generating an Order Form to specify the number of users engaged by this legal entity in the Grinfer for Business service and for making subsequent payments thereof.

The entity named “Customer” therein is a legal body (commercial, non-profit, or government organization) that falls under the obligation of the Grinfer for Business tariff plan thereafter.

The term “Customer’s Users” shall designate the Client’s employees provided by the Customer in the Order Form for which a subsequent payment was made.

The “Order Form” (referred to as “Order” thereafter) shall be sent via the Admin account solely created on the Grinfer platform. This form must contain the exact number of employees referred to as “Customer's Users” herein in addition to all further details provided by the Customer in the Order thereof.

The Recurring Subscription hereunder shall be effective for 1 calendar month commencing as of the Effective Date. The First Subscription Term begins upon the day on which the first payment is made by the Customer for the total number of its Customer’s Users in full compliance with the Order submitted to Grinfer.

The timely commencement of the Grinfer for Business Subscription Plan shall allow legal entities to connect their employees to the Grinfer platform with further extension(s) of successive Subscription terms (unless terminated by the Customer).

The Grinfer for Business service allows both parties, the Customer and the Customer's Users, to get full access to the Grinfer platform with all the available content it provides to its registered users (subjects to the exceptions are specified in the Grinfer Terms of Use policy).

By creating and administering an Admin account on the Grinfer platform, you confirm that you are an official representative of your company and hold legal rights to enter into an Agreement on its behalf and fulfill all related obligations.

As for the Grinfer for Business subscription plan, Grinfer provides the Customer and the Customer's Users with instant access to the platform per number of Customer's Users specified by the Customer in the corresponding Order.

All subsequent payments for gaining access to grinfer.com shall be made on a monthly basis, funds are debited on the first day of the Payment period and deducted from the active payment card linked to the Admin account. The total amount shall be based on the exact number of Customer's Users specified by the Customer in the Order. Customer is solely responsible for all taxes and fees payable in the country of the Customer.

In the event, if the number of Customer's Users changes, the Customer is obliged to make timely changes in the Admin account regarding the number of participants accordingly. In the event of an increase in the number of Customer's Users, while a new Subscription Period has already begun, the Customer shall add a new payment for the new user(s) to the current Subscription Period. A portion of an additional payment is an amount that shall be calculated from the commensurated number of remaining days left until the end of the current Subscription Period.

In the event of a decrease in the number of the Customer's Users occurring because of the exclusion from the Admin account and if this action was executed by the Customer before the expiration date of the current Subscription Term, the initial funds paid for these users will not be refunded during or after the Term.

The Customer acknowledges and agrees that: (a) The Customer is fully liable for the submitted data and any content that the Customer or Customer’s Users contribute in regards to grinfer.com; (b) neither Grinfer nor its Affiliates will be held liable in any way for the preservation of the submitted content; (c) The Customer holds full liability for all actions enacted by the Customer's Users on grinfer.com.

In the case of violation of regulations and standards stated in the Grinfer Terms of Use policy, Grinfer has the right to restrict or terminate access to grinfer.com without further notice or explanation of the cause. The termination of access to the Grinfer platform must be preceded by a fact of violation or infringement caused by actions taken by the Client or the Client's Users. The fact of violation shall be determined by Grinfer hereunder at its sole discretion. In this case, the funds paid by the Customer are non-refundable.

In addition to the above-stated rules, the general Grinfer policies, such as Terms, Privacy, and Copyrights, apply to all users of the Grinfer for Business Recurrent Subscription service.

Modifications to the Grinfer Privacy Policy

In the course of providing Grinfer for Business services, Grinfer shall be given rights to access the Customer's Users personal data for inhouse processing without amendments. The Customer is obliged to submit all the required personal data of its Users to Grinfer and provide access to.

The processing of the Customer's Users' data is performed by Grinfer in accordance with all security measures applied for the sole purpose of full protection of such data from being accessed or used by external parties. All safety precaution measures are detailed and regulated by Grinfer's Privacy Policy.

Grinfer accesses, stores, and uses the Customer's Users personal data solely for the purpose of providing the Grinfer for Business services to a full extent. Grinfer is liable for undertaking the personal data for further processing without amendments in accordance with the Grinfer Privacy policies and regulations.

The Customer shall be liable to determine which of its employees and other authorized personnel will be provided with access to Grinfer for Business services. This procedure shall be accomplished by appointing an Administrator for the Grinfer for Business account (Admin Account), who acts on behalf of the Customer and has the means to open and set up the Customer's account (Admin Account).

The Customer is solely responsible for the full compliance with all applicable laws and regulations stated in the Privacy Policy regarding submitting the personal data of the Customer's Users appointed by the Customer and granted access to the Grinfer for Business services.

The Customer shall confirm hereunder that he has all legal rights to collect and transfer Customer's Users personal data to Grinfer. This includes submitting every User’s full name, surname, e-mail address. In addition, the Customer shall confirm that the consent was received from the Customer's Users stating that they agree to transfer their personal data to Grinfer for further processing, as well as receive any emails from Grinfer to the e-mail addresses that they have submitted to the Customer under consent.

In the event, if the Customer's User inquired Grinfer to remove any personal data completely from the platform and stop processing it, the User must send a request to the Customer first prior to submitting any further requests to Grinfer.


Grinfer provides the following types of discounts:

a. Fixed amount discount

fixed discounts can be received via promotional codes meaning that the user can purchase a course at a reduced price by applying this code to the base price. The promotional code itself is a fixed amount of money or fixed amount of discount given to user which can be redeemed according to the rules of the relevant promo activity.

b. Percent discount

percent discounts allow users to purchase a course at a reduced price when the reduction amount is defined by the promotional code. The final price of the course will be calculated the following way: the original cost of the course minus the certain percentage stated in the promotional code. User can receive this type of discount when making a purchase for his/her use or when gifting the course to another user.

Different types of discounts/ promotional codes can not be combined or applied to one purchase.

In order to receive a discount, the user needs to enter the promotional code on the course page or when placing an order.

Distribution of Promotional codes is carried out as part of the relevant promo activity. The rules of promotional codes distribution, conditions for their receipt, validity periods and other details are described in the rules for the relevant promo activity (promo campaigns).

Discounts that are provided as part of Promotions are not accumulated with other types of discounts. 

The list of courses to which discounts can be applied is located in the rules for each promo activity. Information about active and planned promotions is available https://blog.grinfer.com

Grinfer Referral Program


The Grinfer Referral Program (hereinafter - Referral Program) gives an opportunity for users to earn Referral Program Promotional codes (hereinafter - Referral Promotional codes) for purchasing new courses in the future by bringing friends to purchase courses on Grinfer.

The Referral Program Promotional codes are available to everyone who has a user account at Grinfer.  

How users can earn Referral Promotional codes

Refer a friend and share the referral link via email, text or social media. Your referred friend should create a user account at Grinfer within 48 hours from the moment of clicking on a link. Then, when your referred friend completes a purchase of a course, you will receive a $10 off coupon (Referral Promotional code) for future purchases on Grinfer. In case if your friend opens two referral links one by one before signing up, the referral bonus will be received by the sender of the last opened link.

  • Referred friends are people who signed up using a valid referral link and made a successful purchase on Grinfer.

Referral Promotional сode Terms & Conditions

  1. Referral Promotional codes can be used only on Grinfer.

  2. After receiving a promotional code, it will appear on the Promotional Codes tab in your account. You need to enter a Referral Promotional code on the Course page to apply your discount for this course. 

  3. Discounts on promotional codes distributed through the referral program apply only to courses that participate in the program. When you enter the promotional code on the course page, you will see whether the discount for this promotional code applies to a particular course or not.

  4. Referral Promotional codes issued within Referral Program don’t have an expiration date and can be redeemed at any time. 

  5. Referral Promotional codes are not transferable, may not be resold or redeemed for cash. 

  6. Only one promotional code can be used each time and therefore cannot be combined with other offers using promotional code.

  7. Creating multiple user accounts at Grinfer for getting Referral Promotional codes is prohibited.

  8. Grinfer has the right to require you to submit additional information in order to clarify the validity of your Referral Promotional codes. 

  9. All decisions regarding Referral Promotional codes will be final and at Grinfer’s own discretion. 

Referral links Sharing Conditions

  1. Referrals should only be used for personal purposes, not for commercial. 

  2. You can not spam with invitations sharing referral links (mass emailing or messaging people you don't know). You can not use automated systems or bots to distribute your referral link. 

  3. You can not set campaigns to advertise referral links.

Termination and Changes

  1. Grinfer reserves the right to modify conditions of the Referral Program. Grinfer has the right to suspend or terminate the Referral Program or a user’s ability to participate in it for any reason and without a prior notice.  

  2. However, any promotional codes earned prior to the termination of the Referral Program shall continue to be available until they expire.

  3. Grinfer reserves the right to suspend, delete accounts or remove Referral Promotional codes if we notice any activity that we believe is abusive, fraudulent, or violates any of the Grinfer's Terms and Conditions. 

  4. Grinfer has the right to review and investigate all referral activities and to suspend, delete accounts or modify referrals at our own discretion.

  5. If you have any questions about the Referral Program, please contact us support@grinfer.com.

Payments, Credits, and Refunds

1. To pay for courses and consultations, Grinfer users can use credit and debit cards such as Visa, Mastercard, American Express, etc. Also, we provide users with the possibility to make purchases on Grinfer using PayPal.

2. Refunds for courses and consultations will be transferred to the same card or PayPal account with which the purchase was made.

3. You can claim a refund for a course purchase within 24 hours after buying your course without explanations unless you are willing to give them. For this purpose, please contact our support at support@grinfer.com.

4. Also, you have 14 calendar days to claim a refund for a course in case:

  • The course content does not match the course description

  • The course content is of a poor quality

  • The course was not fully uploaded

  • Please specify other reasons for a purchase refund.

Please contact us at support@grinfer.com with the subject «refund». In the email please state your reason for the refund. In case the reason for the refund does not match the three points mentioned above, it is up to grinfer.com to decide whether to grant you a refund.

5. Please note that it may take up to 5 business days to see funds in your bank account.

6. In case your refund activities look suspicious to the Grinfer support team’s internal regulation, Grinfer.com reserves the right to block your account.

7. Please note that all subscriptions are non-refundable, regardless of reasons. Grinfer will have no refund obligations for any subscriptions purchased by users.


1. Definition. For purposes of these Terms of Use, the term “Content” includes, without limitation, information, data, text, photographs, videos, audio clips, written posts and comments, software, scripts, graphics, and interactive features generated, provided, or otherwise made accessible on or through the Services. For the purposes of this Agreement, “Content” also includes all User Content (as defined below).

2. Notices and Restrictions. The Services may contain Content specifically provided by us, our partners or our users and such Content is protected by copyrights, trademarks, service marks, patents, trade secrets or other proprietary rights and laws. You shall abide by and maintain all copyright notices, information, and restrictions contained in any Content accessed through the Services.

Grinfer grants you (as a learner) a limited, non-exclusive, non-transferable license to access and view the courses and associated content for which you have paid all required fees, solely for your personal, non- commercial, educational purposes through the Services, in accordance with these Terms and any conditions or restrictions associated with a particular courses or feature of our Services. All other uses are expressly prohibited. You may not sell, license, rent, or otherwise use or exploit any Content for commercial use or in any way that violates any third party right. 

You can only use Grinfer for lawful purposes. You’re responsible for all the content that you post on our platform. 

We reserve a right to ban your account for repeated or major offenses, if in our opinion they are such, without prior notice and without explanation. 

If you think someone is infringing your copyright on our platform, let us know.

We generally give a lifetime access license (for the entire duration of the platform) to our learners when they enroll in a course, except when we must delete the course because of legal or copyright or any other policy reasons.

3. Third-Party Services. On the Grinfer you may find links to other websites, services or resources on the Internet. If you choose to access third party resources, you do it at your own risk. We do not control third party recourses, and are not responsible or liable for the content, functions, accuracy, legality, appropriateness or any other aspect of such websites or resources. You further acknowledge and agree that we shall not be responsible or liable, directly or indirectly, for any damage or loss caused or alleged to be caused by or in connection with the use of or reliance on any such content, goods or services available on or through any such website or resource.

How Grinfer and Others May Use User Content

To the extent that you provide User Content, you grant Grinfer a fully-transferable, royalty-free, perpetual, sublicensable, non-exclusive, worldwide license to copy, publicly display, and otherwise use the User Content. Nothing in these Terms shall restrict other legal rights Grinfer may have to User Content, for example under other licenses. We reserve the right to remove or modify User Content for any reason, including User Content that we believe violates these Terms.

Course Modifications

While we take pride in our world-class courses, unexpected events do occur. Grinfer reserves the right to cancel, interrupt, or reschedule any course or to modify any course content or the point value or weight of any assignment, quiz, or other assessment. Courses offered are subject to the Disclaimers and Limitation of Liability sections below.

The content you post as a learner or instructor (including courses) remains yours. We can share your content with anyone through any media (including but not limited to other websites and social media platforms) for any promotional purposes.

The ownership of the content that we have filmed and/or created for any instructor belongs to Grinfer. It is at our sole discretion to remove, add, or edit that video content.


Grinfer’s Rights

We own the Grinfer platform and Services, including the website, present or future apps and services, and things like our logos, API, code, and content created by Grinfer. You cannot use them without approval from Grinfer.

Our platforms and services are protected by copyright, trademark, and other laws. Nothing gives you a right to use the Grinfer name or any of the Grinfer trademarks, logos, domain names, and other distinctive Grinfer features.

Warranty and Other Disclaimers

1. We have no special relationship with or fiduciary duty to you. You acknowledge that we have no duty to take any action regarding:

a. which users gain access to the Services;

b. what Content you access via the Services; or

c. how you may interpret or use the Content.

2. You release us from all liability for you having acquired or not acquired Content through the Services. We make no representations concerning any Content contained in or accessed through the Services, and we will not be responsible or liable for the accuracy, copyright compliance, or legality of material or Content contained in or accessed through the Services.

3. The services and content are provided “as is”, “as available” and without warranty of any kind, express or implied, including, but not limited to, the implied warranties of title, non-infringement, merchantability and fitness for a particular purpose, and any warranties implied by any course of performance or usage of trade, all of which are expressly disclaimed. We, and our directors, employees, agents, suppliers, partners, and content providers do not warrant that: (i) the services will be secure or available at any particular time or location; (ii) any defects or errors will be corrected; (iii) any content or software available at or through the services is free of viruses or other harmful components; or (iv) the results of using the services will meet your requirements. your use of the services is solely at your own risk. some states do not allow limitations on implied warranties, so the foregoing limitations may not apply to you.

We do not guarantee that the services will function without interruption or errors. in particular, the operation of the services may be interrupted due to maintenance, updates, or system or network failures, and such failures may result in errors or data loss. we disclaim all liability for damages caused by any such interruption or errors in functioning, or by the loss of any data or information you provide to us. furthermore, we disclaim all liability for any malfunctioning, impossibility of access, or poor use conditions of the services due to inappropriate equipment, disturbances related to internet service providers, to the saturation of the internet network, and for any other reason.

Limitation of liability 

You expressly understand and agree that Grinfer and any contributor to the user generated content via Grinfer SHALL NOT BE LIABLE to you for:

1. any loss or damage which you may incur, including without limitation as a result of any reliance placed by you on the accuracy, completeness or suitability of the Content, or any changes Grinfer may make to the Websites, Online Mediums and Content, or any temporary interruption or permanent cessation in the provision of the Online Mediums and Content, or, if applicable, your failure to safeguard your account details or passwords.

2. to the full extent permitted by law, Grinfer is not liable for any direct, indirect, special, incidental, consequential, punitive or exemplary damages arising out of or in connection with your use of or related to the Websites, Online Mediums and Content (including without limitation for loss of or damage to business, revenues, goodwill or data) even if Grinfer had previously been advised of, or reasonably could have foreseen, the possibility of such damages, however they arise, whether in breach of contract, negligence or other tortuous action. 

3. You acknowledge and agree that the disclaimers and the limitations of liability set forth in this terms of use reflect a reasonable and fair allocation of risk between you and the Grinfer parties, and that these limitations are an essential basis to grinfer's ability to make the services available to you on an economically feasible basis.

You agree that any cause of action related to the services must commence within one (1) year after the cause of action accrues. otherwise, such cause of action is permanently barred.

Copyright infringement liability limitation

You agree that copyright owners personally provide adequate and effective protection to protect their works.

Limitations on liability for copyright infringement by online service providers. The limitations are based on the following four categories of conduct by a service provider:

  1. Transitory communications;

  2. System caching;

  3. Storage of information on systems or networks at direction of users;

  4. Information location tools.

You agree that Grinfer exempt from any liability for copyright infringement. 

The copyright owner personally must still demonstrate that any person has infringed, and Grinfer may still avail itself of any of the defenses, such as fair use, that are available to copyright defendants generally. 

You agree that Grinfer doesn't monitor its services or access material in violation of law in order to be eligible for any of the liability limitations.

You agree that Grinfer limits his liability for the practice of retaining copies, for a limited time, of material that has been made available online by a person other than the provider, and then transmitted to a subscriber at his or her direction. Grinfer retains the material so that subsequent requests for the same material can be fulfilled by transmitting the retained copy, rather than retrieving the material from the original source on the network.

The benefit of this practice is that it reduces the service provider’s bandwidth requirements and reduces the waiting time on subsequent requests for the same information. 

In addition, Grinfer is protected from any liability to any person for claims based on its having taken down the material. 

Penalties are provided for knowing material misrepresentations in either a notice or a counter notice.

Any person who knowingly materially misrepresents that material is infringing, or that it was removed or blocked through mistake or misidentification, is liable for any resulting damages (including costs and attorneys’ fees) incurred by the alleged infringer, the copyright owner or its licensee, or Grinfer.


You agree to indemnify and hold Grinfer, officers, shareholders, directors, agents, employees and representative from any claims and demands, including reasonable attorneys’ fees, made by any third party arising from or relating to:  (i) your use of and access to the Websites, Online Mediums and Content; (ii) content you submit, post, transmit or otherwise make available via the Website and Online Mediums; (iii) your violation of these Terms. This indemnification obligation will survive the termination of your Grinfer account or these Terms.

Dispute Resolution and Arbitration

Applicable law

Dutch law applies to this website and the disclaimer. All disputes arising from or in connection with this disclaimer will be submitted exclusively to the arbitrated in the Netherlands.

Dispute Resolution

In the event of a Dispute, you or Grinfer must give the other a written statement that sets forth the name, address, and contact information of the party giving it, the facts giving rise to the Dispute, and a proposed solution (a "Notice of Dispute"). You must send any Notice of Dispute by Mail to Grinfer at Kamer241, Keizersgracht 241, 1016 EA Amsterdam, The Netherlands and also via e-mail to support@grinfer.com. Grinfer will send any Notice of Dispute to you by Mail to your address if Grinfer has it, or otherwise to your e-mail address. You and Grinfer will attempt in good faith to resolve any Dispute through informal negotiation within sixty (60) days from the date the Notice of Dispute is sent. After sixty (60) days, you or Grinfer may commence arbitration.



Dispute which has not been resolved by negotiation as provided herein within sixty (60) days or such time period as you and Grifer may otherwise agree, shall be finally resolved by binding arbitration.

Class Action Waiver. 

If we can’t resolve our dispute amicably, and Dispute which has not been resolved by negotiation as provided herein within sixty (60) days or such time period as you and Grinfer agree to resolve any claims related to these Terms (or our other legal terms) through final and binding arbitration, regardless of the type of claim or legal theory. If one of us brings a claim in court that should be arbitrated and the other party refuses to arbitrate it, the other party can ask a court to force us both to go to arbitration (compel arbitration). Either of us can also ask a court to halt a court proceeding while an arbitration proceeding is ongoing.

We both agree that we can each only bring claims against the other on an individual basis. This means: 

  1. neither of us can bring a claim as a plaintiff or class member in a class action, consolidated action, or representative action; 

  2. an arbitrator can’t combine multiple people’s claims into a single case (or preside over any consolidated, class, or representative action);

  3. an arbitrator’s decision or award in one person’s case can only impact that user, not other users, and can’t be used to decide other users’ disputes. If a court decides that this “No class actions” clause isn’t enforceable or valid, then this “Dispute Resolution” section will be null and void, but the rest of the Terms will still apply.

The parties shall not involve any personal appearance by the parties or witnesses, unless otherwise mutually agreed by the parties; rather, the arbitration shall be conducted, at the option of the party seeking relief, online, by telephone, or via written submissions alone. 

Modifications to These Terms

We reserve the right, in our sole discretion, to modify Terms of Service, or change or discontinue the Services (including without limitation, the availability of any feature, database, or content) at any time without liability. We will notify you about updates through the website, via e-mail or by any other means of electronic communication. But you also responsible for checking these Terms of Service periodically for changes.

We also reserve the right to limit access to certain features, services or to parts or all of the Services without notice or liability.

Your continued use of Grinfer and its Services after updates become effective mean that you accept those changes. Any updated Terms supersede all previous Terms.

How to Contact Us

If you have any questions, concerns, and feedback, drop a line to our Support Team or contact us at the following address: Kamer241, Keizersgracht 241, 1016 EA Amsterdam, The Netherlands.


We welcome your suggestions, ideas, comments, and other feedback regarding the Services ("Feedback"). By submitting any Feedback, you grant us the right to use the Feedback without any restriction or any compensation to you. By accepting your Feedback, Grinfer does not waive any rights to use similar or related Feedback previously known to Grinfer, developed by its employees or contractors, or obtained from other sources.

*Age varies by country or region.