เงื่อนไขใบอนุญาตการใช้งานอีบุ๊ก

1. Parties and Scope

This Ebook End-User License Agreement ("License") is a legal agreement between you ("Licensee") and Peera Lertsukittipongsa, operating as Painkiller School ("Licensor"), governing your use of any ebook, PDF, HTML publication, EPUB3 file, or downloadable digital publication ("Ebook") purchased or downloaded through the Platform at painkiller.school.

By downloading, opening, reading, or otherwise accessing an Ebook, you agree to be bound by the terms of this License.

2. Grant of License

Subject to your compliance with this License and full payment (or email registration for free ebooks), the Licensor grants you a personal, non-exclusive, non-transferable, non-sublicensable, revocable license to download, access, and read the Ebook solely for your own personal, non-commercial use and study. This License is granted to you as an individual and does not transfer to any other person.

3. Permitted Uses

• Download the Ebook to up to three (3) personal devices that you own or control;
• Read the Ebook for your own personal learning and reference;
• Print a single copy for your own personal use only, provided the printed copy is not distributed to others;
• Bookmark, highlight, and annotate the Ebook in any reading application for your own study purposes.

4. Prohibited Uses

You may NOT:

• Redistribute or share the Ebook (in whole or in part) with any third party, whether free of charge or for payment, in any format or medium;
• Sell, resell, rent, lease, or otherwise commercially exploit the Ebook or any portion of it;
• Sublicense or otherwise transfer your rights under this License to any other person;
• Modify, adapt, translate, or create derivative works based on the Ebook without the Licensor's prior written consent;
• Remove, alter, or obscure any copyright notice, watermark, license information, HMAC signature, or other proprietary marking embedded in or displayed within the Ebook;
• Use the Ebook or any portion of its content to train, fine-tune, instruct, develop, or improve any artificial intelligence system, machine learning model, large language model, or generative AI tool, whether for commercial or non-commercial purposes;
• Use the Ebook for any commercial purpose, including but not limited to incorporating its content into courses, workshops, or other paid products or services;
• Circumvent any technical protection measures (encryption, signed URLs, digital watermarking, HMAC signature verification) applied to the Ebook.

5. Digital Watermarking: Individually Licensed, Tamper-Evident Files

Every Ebook sold or made available through the Platform (in all formats: PDF, HTML, EPUB3) is individually licensed and contains an embedded, per-customer digital watermark. The watermark is generated and injected automatically at the moment each download link is issued. There is no opt-out.

The watermark contains, at minimum: your email address; your order ID or download session ID; the exact date and time of download link generation (UTC timestamp); and an HMAC-SHA256 cryptographic signature binding the above fields to this specific file instance.

The watermark renders each file tamper-evident and uniquely traceable to its licensed recipient. If an unauthorized copy of any Ebook is discovered, the embedded watermark and HMAC-SHA256 signature will be used to identify the source of the unauthorized distribution and to support legal enforcement action.

Removing, altering, or otherwise attempting to defeat the watermark or HMAC signature is: (a) a material breach of this License, causing it to terminate immediately; (b) a potential violation of the Computer Crime Act B.E. 2550 (2007) of Thailand; and (c) a potential violation of the Copyright Act B.E. 2537 (1994) of Thailand.

6. Free Email-Gated Downloads

All terms of this License (including Sections 4 (Prohibited Uses) and 5 (Digital Watermarking)) apply in full to Free Ebooks. The absence of a monetary purchase price does not affect the enforceability of this License or the legal consequences of unauthorized distribution.

Your email address collected at the download gate will not be used for marketing communications unless you separately and actively opt in.

7. Intellectual Property

The Ebook and all content within it is the exclusive intellectual property of Peera Lertsukittipongsa and is protected under the Copyright Act B.E. 2537 (1994) of Thailand and international copyright treaties. This License does not transfer any ownership of intellectual property to you.

8. Term and Termination

This License will terminate automatically, without notice, if you breach any provision. Upon termination, you must immediately cease all use of the Ebook and delete all copies from your devices. Termination does not entitle you to a refund.

9. Governing Law and Enforcement

This License is governed by the laws of the Kingdom of Thailand. Disputes arising under this License shall be subject to the exclusive jurisdiction of the courts of Bangkok, Thailand. Unauthorized use, redistribution, or tampering with an Ebook may result in civil liability under the Copyright Act B.E. 2537 and/or criminal liability where applicable.

10. Contact

Peera Lertsukittipongsa, Painkiller School
Email: [email protected]
Website: painkiller.school
For bulk license inquiries (educational institutions, commercial use), contact us at the email above.