In March 2007, PUBPAT filed formal requests with the United States Patent and Trademark Office challenging four key HIV/AIDS drug patents held by Gilead Sciences, Inc. (NASDAQ: GILD). As part of its requests, PUBPAT submitted prior art that the Patent Office did not review before granting the patents to the Foster City, California, biopharmaceutical giant. PUBPAT also explained how the submitted prior art invalidates the patents and asked that the Patent Office undertake a review and revoke them. In July 2007, the Patent Office granted each of PUBPAT's requests and ordered reexamination of all four patents. In December 2007 and January 2008, the Patent Office rejected all of the claims of each of the patents.

In July 2006, PUBPAT filed formal requests with the United States Patent and Trademark Office on behalf of the Foundation for Taxpayer and Consumer Rights to revoke three patents owned by the Wisconsin Alumni Research Foundation that purport to cover stem cells that are looting taxpayer funds and forcing research overseas. In its filings, PUBPAT submitted previously unseen prior art showing that the patents were - in fact - not new and, as such, should be revoked. The USPTO granted each of the requests in September 2006 and rejected all claims of each of the patents on March 30, 2007. In June 2007, PUBPAT submitted comments to the Patent Office supporting the rejections. The proceedings are currently ongoing.

In September 2006, PUBPAT filed formal requests with the United States Patent and Trademark Office to revoke four patents owned by Monsanto Company that the agricultural giant is using to harass, intimidate, sue - and in many cases bankrupt - American farmers. In its filings, PUBPAT submitted prior art showing that the patents were undeserved and, as such, should be revoked. The U.S.P.T.O. granted each of those requests in November 2006, finding that PUBPAT had raised "substantial new questions of patentability" with respect to every claim of each patent. In February, May, June and July 2007, the Patent Office issued complete rejections of all four patents.

In January 2007, PUBPAT filed a formal request with the United States Patent and Trademark Office to review a patent held by Patriot Scientific (OB: PTSC) that the company, which boasts of "primarily focusing on deriving revenue from licensing patents", is widely asserting against producers of computer microprocessors. In its filing, PUBPAT submitted prior art that the Patent Office was not aware of when reviewing the application that led to the issuance of the patent, described in detail how the prior art invalidates the patent and asked that the patent be revoked. In April 2007, the Patent Office granted PUBPAT's request for reexamination of the patent.

In January 2007, PUBPAT filed a formal request with the United States Patent and Trademark Office to review a patent held by Opsware Inc. (NASDAQ: OSPW) that relates to remote computer management, but was preempted by the work of open source projects. In its filing, PUBPAT submitted prior art that the Patent Office was not aware of when reviewing the application that led to the issuance of the patent (U.S. Patent No. 7,124,289), described in detail how the prior art invalidates the patent and asked that the patent be revoked. In April 2007, the Patent Office granted PUBPAT's request for reexamination of the patent.

In November 2006, PUBPAT filed formal requests with the United States Patent and Trademark Office to review two patents held by epicRealm Licensing Inc. that the patent licensing company - which offers no products or services - is widely asserting against providers of dynamic websites, i.e. websites that can produce custom responses to individual visitors or users. In its filings, PUBPAT submitted prior art that the Patent Office was not aware of when reviewing the applications that led to the two patents, described in detail how the prior art invalidates the patents and asked that the patents be revoked. In January, 2007, the Patent Office granted PUBPAT's requests.

PUBPAT filed a formal request with the United States Patent and Trademark Office in November 2005 to revoke the patent Forgent Networks Inc. (Nasdaq: FORG) is widely asserting against the Joint Photographic Experts Group (JPEG) international standard for the electronic sharing of photo-quality images. In its filing, PUBPAT submitted previously unseen prior art showing that the patent, which was issued in 1987 to Forgent's subsidiary Compression Labs Inc., was not new and, as such, should be revoked. The PTO granted PUBPAT's request in February 2006 and rejected the broadest claims of the patent in May 2006. In November 2006, Forgent abandoned all assertion of the patent.

In September 2004, the Public Patent Foundation filed a formal request with the United States Patent and Trademark Office to revoke Pfizer Inc.'s patent on Lipitor, touted by the pharmaceutical giant as being "the best-selling treatment for lowering cholesterol and the best-selling pharmaceutical product of any kind in the world." In its filing, PUBPAT submitted prior art showing the patent, which issued in October 1999 and is not otherwise due to expire until 2016, was anticipated by earlier work of other inventors and, as such, should have never been granted. The PTO granted PUBPAT's request in December 2004 and rejected the patent in June 2005. In November 2005, Pfizer conceded to give up its original broad claims.

In April 2004, the Public Patent Foundation filed a formal request with the United States Patent and Trademark Office to revoke Microsoft Corporation's patent on the FAT File System, touted by Microsoft as being "the ubiquitous format used for interchange of media between computers, and, since the advent of inexpensive, removable flash memory, also between digital devices." In its filing, PUBPAT submitted previously unseen prior art showing the patent, which issued in November 1996 and is not otherwise due to expire until 2013, was obvious and, as such, should have never been granted. The PTO granted PUBPAT's request in June 2004 and rejected the patent in September 2004.

In February 2004, PUBPAT filed a request for reexamination of Columbia University's patent on cotransformation, a process for inserting foreign DNA into a host cell to produce certain proteins that is the basis for a wide range of pharmaceutical products, including Epogen for anemia, Activase for heart attacks and stroke, Avonex for multiple sclerosis and Recombinate for hemophilia. PUBPAT's requrest showed that the patent, issued in 2002, violates the restriction against multiple patenting because Columbia previously received three other patents for the same invention in the 80's and early 90's. The three previous patents expired in 2000; the new patent will not expire until 2019. The Patent Office granted PUBPAT's request in May 2004 and Columbia voluntarily waived any right to assert the patent in December 2004.