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.
EaseFilter
EaseFilter specialize in file system filter driver development. They architect, implement and test file system filter drivers for a wide range of functionality. EaseFilter can offer several levels of assistance to meet your specific needs; providing consulting services for your existing file system filter driver, offering customization of their SDKs to meet your requirements or assistance to create your own filter driver with their source code.
ActivePDF
ActivePDF provides a suite of easy to use, cost effective development tools for embedding feature-rich PDF functionality into server-based Windows applications. ActivePDF delivers robust, multithread, server-side PDF automation products which are intended for heavy-duty, enterprise-wide use. When you need it done now, need it done right, and need it every time, then ActivePDF provides the product, the support, and the level of confidence you need.