Patent and Trademark Depository Library Program

The United States Patent and Trademark Office has a network of public, state, and academic libraries nationwide designated as Patent & Trademark Depository Libraries (PTDL).   The State Library became Iowa's PTDL in 1988.  As a PTDL, the U.S. Patent and Trademark Office provides us with their databases and software, official manuals, handbooks, and search tools to provide resources and assistance for Iowa's patent and trademark clientele.