Comparison

ATick vs other PDF signing libraries

An honest, researched comparison. ATick is one signing engine with the same API in Python, Java, .NET, Node.js and PHP — and it ships the things rivals either dropped, never had, or charge for.

What only ATick gives

CapabilityATickEveryone else
Adobe-valid green-tick appearance Built-in, currentOnly iText had it — now deprecated; no other library ships it
One API across 5 languages Python, Java, .NET, Node.js, PHPEvery rival is single-language / single-platform
Windows certificate-store connector Built-in, in every languageOnly IronPDF (.NET) has a one-liner; everyone else is DIY
Free AND batteries-included Yes — AGPL-3.0 (commercial only to resell)Turnkey rivals (iText, IronPDF, Apryse, SetaPDF) are paid; the free turnkey one (pyHanko) is Python-only
Certified no-changes (certify=1) + LTV + encrypted Built-in combinationRare or manual to combine elsewhere

The in-document Adobe green tick was a one-tag feature only in iText 5; iText 7/8 still expose SetAcro6Layers but deprecated it, and no other library implements it. ATick is the only one that ships it as a current feature.

PDF signing in Python

ATick vs pyHanko and endesive (both free, MIT).

FeatureATickpyHankoendesive
PAdES B-LTA (named levels)Partial
Built-in RFC-3161 timestamp
Built-in LTV / DSS (one call)OCSP only
Adobe-valid green-tick appearance
Windows cert-store connector (built-in)
PKCS#11 / smart-card / HSM
Deferred / remote / eSign
Encrypted output + sign
Free licenseAGPLMITMIT

ATick for Python docs →

PDF signing in Java

ATick vs iText 7 and Apache PDFBox.

FeatureATickiText 7PDFBox
PAdES B-LTA (named levels)Manual
Built-in RFC-3161 timestampManual
Built-in LTV / DSS (one call)Manual
Adobe-valid green-tick appearanceDeprecated
Windows cert-store connector (built-in)
PKCS#11 / smart-card / HSMDIY
Deferred / remote / eSignManual
Encrypted output + signLimited
Free licenseAGPLAGPL / PaidApache-2.0

ATick for Java docs →

PDF signing in .NET

ATick vs iText 7, IronPDF and Apryse (PDFTron).

FeatureATickiText 7IronPDFApryse
PAdES B-LTA (named levels)Assembled
Built-in RFC-3161 timestamp
Built-in LTV / DSS (one call)
Adobe-valid green-tick appearanceDeprecated
Windows cert-store connector (built-in)DIYManual
PKCS#11 / smart-card / HSMCustom
Deferred / remote / eSign
Encrypted output + signUnclear
Free licenseAGPLAGPL / PaidPaidPaid

ATick for .NET docs →

PDF signing in Node.js

ATick vs @signpdf / node-signpdf and pdf-lib — the Node ecosystem has no full PAdES/LTV signer.

FeatureATick@signpdfpdf-lib
PAdES B-LTA (named levels)B-B only
Built-in RFC-3161 timestamp
Built-in LTV / DSS (one call)
Adobe-valid green-tick appearance
Windows cert-store connector (built-in)
PKCS#11 / smart-card / HSM
Deferred / remote / eSignDIY
Encrypted output + sign
Free licenseAGPLMITMIT

ATick for Node.js docs →

PDF signing in PHP

ATick vs SetaPDF-Signer (commercial) and TCPDF (free, deprecated).

FeatureATickSetaPDF-SignerTCPDF
PAdES B-LTA (named levels)Compose
Built-in RFC-3161 timestamp
Built-in LTV / DSS (one call)Multi-step
Adobe-valid green-tick appearance
Windows cert-store connector (built-in)
PKCS#11 / smart-card / HSMAdd-on
Deferred / remote / eSign
Encrypted output + sign
Free licenseAGPLPaidLGPL

ATick for PHP docs →

The honest verdict

The rivals are good at what they do: pyHanko (Python) is a free, standards-rigorous library with automatic LTV and timestamping; iText, Apryse and SetaPDF-Signer are powerful, production-grade products. But each is single-language, none ships a current Adobe-valid green tick, and the turnkey ones are paid (or AGPL).

ATick's edge is the combination no one else offers: one API in five languages, a current Adobe-valid green-tick appearance, a built-in Windows certificate-store connector, and a full PAdES-B-LTA / LTV / certify / encrypted pipeline that is free under AGPL-3.0 (a commercial license is only needed to resell it). In Node.js especially, there is no comparable full PAdES/LTV signer at all.

Start with the documentation or read about PAdES & LTV.

Comparison researched against each project's official documentation at the time of writing — check their docs for the latest. ATick is free under AGPL-3.0.