did some company file a lawsuit against them?
Yes, Pfizer
Icos
Pfizer 
what is icos? It was an American biotechnology company. where exactly was it located? U.S. state of Washington when was it founded? 1989 who founded it? David Blech, Isaac Blech, Robert Nowinski, and George Rathmann what drugs were manufactured there? Drugs to treat inflammatory disorders, antibodies, tadalafil, LeukArrest ect
wiki:341415
Icos [SEP] Lawsuits with Pfizer
Pfizer and Lilly Icos have filed many lawsuits against each other in various countries over Cialis and Viagra. Pfizer was given a broad patent on PDE5 inhibitors in Britain in 1993. Lilly Icos filed a complaint in a London court in September 1999, and the patent was overturned in November 2000 on the grounds that Pfizer's patent was based on information already in the public domain when the patent was issued. In the United States, Pfizer filed suit against Lilly Icos soon after receiving a broad US patent for PDE5 inhibitors in October 2002. The United States Patent and Trademark Office ordered a reexamination of the patent, and, as in Britain, the examiner found that PDE5 inhibitors were not a new invention by Pfizer, voiding the patent.