These Terms of Use and Disclaimer ("Terms") explain the rules that apply to the Monstera PDF Editor project website at monsterapdf.com (the "Website"), voluntary financial support, and related communications. They also provide important information about the Monstera PDF Editor application ("Monstera"). Monstera is developed and distributed by Tenslor Inc., a Delaware corporation ("Tenslor", "we", "us", or "our").
Monstera is free and open-source software licensed under the GNU Affero General Public License, version 3 or any later version (AGPL-3.0-or-later).
Your copyright licence to the software is governed by the AGPL, not by a separate commercial End User Licence Agreement or by contractual restrictions on use invented in these Terms. If any statement in these Terms conflicts with rights granted by the AGPL, the AGPL controls with respect to the covered software.
1Scope of these Terms
These Terms govern your use of the official Website and describe the arrangements for Website content, project communications, voluntary donations, and external links. The terms of the AGPL and relevant third-party licences govern your rights to use, copy, study, modify and redistribute the covered software. The requirements of a third-party AI provider, cloud account, signature service, or payment platform apply separately to that provider's service.
We do not require you to create a Tenslor account or accept an additional software EULA simply to exercise rights provided by the AGPL. Nothing in these Terms removes statutory consumer or other rights that cannot lawfully be excluded.
2Free software and your rights under the AGPL
Monstera is made available free of charge under AGPL-3.0-or-later. Subject to that licence, you may run the covered program for any purpose, inspect and modify the source code, and share original or modified copies. Distribution, conveyance, modified versions, and applicable network-interaction scenarios may trigger source-code and notice obligations under the AGPL. The full licence, rather than this summary, states the applicable requirements.
Read the GNU Affero General Public License (opens in a new tab).
Monstera is distributed through the Microsoft Store. The applicable Store listing and software materials should identify the AGPL as the software licence. To the extent the Store ordinarily supplies standard application licence terms, the separately supplied open-source licence is intended to govern the covered software.
3Source code and third-party open-source components
The official source repository, release materials, and applicable notices are identified on the Website's Third-Party Notices and Source page. The project is intended to make available the corresponding source materials required by its applicable licences for the software it distributes. The actual contents of each release and the notices accompanying it control.
Monstera incorporates third-party components, including MuPDF, Ghostscript, ONLYOFFICE, Poppler, PDFium, PDF.js, Tesseract and other open-source software. Each component remains subject to its own licence and notice requirements. The Website's summary of component licences is informational; the licences, notices, source materials and additional terms shipped with the relevant component version govern that component.
If you identify missing corresponding source, an incorrect licence notice, or other apparent compliance issue, contact report@monsterapdf.com. We treat such reports as matters requiring review and correction.
4Website content and intellectual property
The Website contains explanations, images, documentation, product descriptions, branding, and other materials. Except for materials explicitly identified as licensed under an open-source licence or otherwise made available for reuse, the Website's creative content remains subject to applicable copyright and intellectual-property law.
The AGPL licence of the application does not automatically apply to every photograph, illustration, Website design element, logo, or written description on the Website. Any reuse of software code or separately licensed materials is governed by their applicable licences. You may link to the Website and accurately describe Monstera and its features, subject to applicable law.
5Product availability, downloads, and updates
The official Windows application is offered through the Microsoft Store. The Website does not itself distribute a Windows installer. Exercise caution with unofficial installers or websites claiming to offer an authorised installation package. We do not promise uninterrupted Store availability, that every feature is available on every Windows device, or that third-party services will remain available indefinitely.
Microsoft handles Store distribution, installation, updates, and its own payment, account, and diagnostic arrangements under its applicable terms and privacy notices. Software updates may change or remove features. They do not retrospectively cancel the open-source rights you received in copies already distributed under the AGPL.
6Use of documents and responsibility for output
Monstera provides document editing, conversion, recognition, redaction, form, signature, and other processing tools. You determine whether you have authority to open, process, modify, sign, upload, or share a particular document. You are responsible for ensuring that your use respects confidentiality, privacy, copyright, records-management, and other applicable obligations.
Keep original copies of important documents and verify outputs before sending, publishing, filing, signing, archiving or relying on them. Format conversion, OCR, edits, compression, accessibility remediation, signatures and other processing operations may introduce errors or loss of information. The application does not determine whether an output is legally valid, complete, compliant, or suitable for your circumstances.
7Redaction, signatures, and security-sensitive functions
Redactions
Monstera's redaction tools are designed to remove the underlying content, rather than merely place a visible covering over it. Redaction nevertheless requires care. Before disclosing a redacted file, reopen the final output and verify that hidden text, metadata, annotations, attachments, recoverable objects, and other sensitive content have been removed as required for your purpose. Do not rely solely on the appearance of black boxes.
Digital signatures
You are responsible for confirming that your signing certificate is valid, appropriate for your transaction and legally recognised where necessary. Verify the signature, signer identity, trust chain, timestamp and document integrity before relying on any signed document. Adding a visible signature image alone does not necessarily create a legally recognised digital signature.
Passwords, permissions and sandboxing
Document permissions, encryption, and application sandboxing provide protections within their stated scope. They cannot guarantee that every malicious file, attack, unauthorised recipient, or error will be prevented. Check that a protected file opens and behaves as expected in its intended environment.
8AI, OCR, handwriting and other automated features
Monstera may use AI models, OCR engines, handwriting recognition, and other automated techniques. Their results can be inaccurate, incomplete, misleading, or unsuitable for a particular purpose, including when they include source references. You must independently review important output and check quotations, figures, inferred facts, translations and summaries against their source documents.
Monstera is not a provider of legal, medical, financial, accounting, or other regulated professional advice. Its tools and AI outputs do not replace consultation with a qualified professional. You must not treat generated text or document analysis as a professional certification or guarantee of legal compliance.
Monstera's AI features use your own supported provider credentials and are optional. Information submitted directly to an AI or cloud provider is subject to that provider's terms, prices, usage limits, retention practices, and privacy notices. Provider fees, if any, are payable under your arrangement with that provider; they are not a Monstera subscription. Review confidentiality and privacy requirements before transmitting sensitive data. See the Privacy Policy for the feature-specific connection table.
9External services and links
Optional features may involve providers such as the following. These providers operate independently under their own terms, including requirements for credentials, permissions, charges, data handling, and availability.
- Anthropic
- OpenAI
- Google (Gemini)
- Mistral
- xAI
- Microsoft Azure OpenAI
- OpenRouter
- Groq
- Perplexity
- DeepSeek
- Microsoft Azure Document Intelligence
- DigiCert
- GlobalSign
- Sectigo
- DocuSign
- Google Drive
- Microsoft (OneDrive sign-in)
- Microsoft Store
- Stripe (website donations only)
The Website may also link to GitHub, Microsoft Store, Stripe, and other websites. A link is provided for convenience or context and does not mean Tenslor controls or endorses all content, conduct, or policies on the destination site.
10Voluntary donations and recurring support
Monstera is free software, and donations are voluntary. A contribution is not required to download or use Monstera and does not grant additional features, remove restrictions, purchase a software licence, or entitle the donor to priority technical support, guaranteed releases, or influence over development decisions. Donors and non-donors receive the same core software under the AGPL.
Contributions are handled through Stripe, our payment provider. The amount, payment method, currency, payment processing, recurring billing, cancellation mechanism and available refund or dispute options are governed by the transaction terms and applicable law, as well as the information presented when you contribute. If you authorise recurring support, it may renew automatically until cancelled through the payment provider; cancelling ordinarily stops future renewals, subject to the payment provider's rules.
Voluntary contributions are generally non-refundable once processed, but this does not override applicable law, the payment provider's procedures, or remedies for unauthorised, duplicate or mistaken payments. For payment issues, contact us at support@monsterapdf.com where our assistance is needed.
The donation entry within the application is labelled "Donate", on the top row and in the Help menu. It opens monsterapdf.com/donate in your browser. The application itself does not process the payment.
Tenslor Inc. is a for-profit company, not a registered charity. Contributions should not be represented as charitable or tax-deductible donations unless independent tax advice confirms that treatment for your circumstances. Making a contribution does not convert your AGPL licence into a paid commercial licence. Any payment or recurring-support relationship remains subject to the applicable transaction terms and mandatory consumer law.
11Support and responsible disclosure
We offer user assistance and community support on a reasonable-efforts basis. Unless we separately agree to written service terms, no particular support response time, repair deadline, release date, or guaranteed result is promised.
For bugs and vulnerabilities, use the contact routes on our Support page. If you discover a suspected security flaw, report it privately and avoid publishing exploit details or exposing third-party information before an appropriate review. This request is for responsible coordination and does not diminish lawful security research or rights under the AGPL.
Please do not send confidential documents or sensitive personal data unless necessary for the request; use a redacted or synthetic sample where possible. Our Privacy Policy explains how we handle information voluntarily sent to us.
12Trademarks and official releases
The AGPL governs the licensing of the applicable software code. It does not grant trademark rights.
"Monstera", "Monstera PDF Editor" and the Monstera logo are trademarks of Tenslor Inc. All rights are reserved in those trademarks.
You are free to modify and distribute Monstera in accordance with the AGPL.
However, a modified version must not be presented as the official Monstera release or otherwise imply that Tenslor Inc. created, approved, endorsed or distributed the modified version when that is not the case.
A modified build should use a different name and logo so that users can distinguish it from the official Monstera software.
It is permissible to accurately state that a modified product is based on or derived from Monstera, provided the statement does not create a false impression of official endorsement or affiliation.
Third-party product names mentioned on the Website are the property of their respective owners; references identify integrations or comparisons and do not imply sponsorship or endorsement.
13Website information and product comparisons
Website material is supplied for general information. We try to keep descriptions and comparisons accurate but features, availability, compatibility and third-party products can change. Product comparisons reflect their stated methodology and review date, where provided; users should check important details with the relevant provider before making consequential decisions.
No statement on the Website should be taken as a guarantee that Monstera satisfies every legal, regulatory, accessibility, records-retention, or professional requirement for your particular use case.
14Warranty disclaimer and limits of liability
For covered software, the GNU AGPL's own Sections 15 and 16 contain the governing warranty disclaimer and limitation of liability, subject to applicable law. To the extent allowed by those provisions and by mandatory law, Monstera is provided "as is", without a promise that it will be uninterrupted, error-free, secure against every possible threat, or fit for any particular purpose. You bear responsibility for preserving your original documents and assessing the suitability of your results.
The Website and related informational resources are likewise provided on a reasonable-efforts, "as available" basis to the fullest extent permitted by applicable law. Tenslor does not guarantee uninterrupted availability or the accuracy of third-party information, links, or independently operated services.
To the maximum extent permitted by applicable law, Tenslor and the relevant contributors are not liable for indirect or consequential losses arising from Website use or from reliance on unsupported outputs, such as lost profits, business interruption, or data loss, except to the extent liability cannot lawfully be excluded. We do not exclude or limit liability for fraud, wilful misconduct, death or personal injury caused by negligence where such exclusion is prohibited, or any other liability that cannot legally be limited. For software copyright-licence matters, the AGPL prevails over inconsistent statements in this section.
15Changes to the Website and these Terms
We may correct or update Website information, service links, or these Terms to reflect operational or legal changes. The current version and effective date will appear on this page. Material changes may be highlighted through the Website or release notes when appropriate. Such changes do not revoke AGPL rights already granted in software copies you have received.
16Governing law and mandatory rights
To the extent these Terms independently govern the Website and related interactions, they are interpreted under the laws of the State of Delaware, United States, without giving effect to conflict-of-laws principles, unless mandatory law provides otherwise. This is not an agreement to an exclusive court location or a waiver of consumer rights or legal remedies guaranteed by the laws that apply to you.
Copyright-licence rights and obligations in Monstera remain subject to the AGPL. Your dealings with independent payment, cloud, AI and other service providers may be subject to their own valid governing-law provisions.
17Contact
For general legal questions: support@monsterapdf.com
For bugs and security concerns: report@monsterapdf.com
Tenslor Inc., a Delaware corporation
See the Privacy Policy, Third-Party Notices and Source, and Support pages.