ComPDFKit
ComPDFKit enable developers to integrate PDF Annotations and Format Conversion, Digital Signature, Smart Forms, OCR, Redaction, and more in to their applications on Windows, macOS, iOS, Android, and the web through their PDF SDKs. Their aim is to offer the most comprehensive library to shorten the project development cycle and to continuously improve their SDK products to meet developer's future requirements as they change and projects evolve.
PDFlib
PDFlib GmbH is completely focused on PDF technology. Customers worldwide use PDFlib products since 1997. The company closely follows development and market trends, such as ISO standards for PDF. PDFlib GmbH products are distributed in more than 100 countries all over the world with major markets in North America, Europe, and Japan.
Investintech
Investintech.com Inc. is a Canadian company incorporated in 2000, who are the developer and publisher of their own proprietary PDF technology. It's used in desktop, server and developer products worldwide. Millions in over 150 countries have used their flagship PDF product Able2Extract. As a company, they are focused on providing business and consumer customers with products that are easy to use and that deliver powerful results. All the products are built by in-house software development teams headquartered in Toronto, Canada and in Investintech's European office.