George Graff and Adam Kraidin have written a concise article for the Washington Legal Foundation that neatly summarizes current law on submarine patents. Submarine patents use successive continuation applications to claim previously disclosed but unclaimed features of an invention many years after the filing of the original application. Ricoh v. Nashua (Fed. Cir. 1999).
Most recently, the Nevada District Court in Symbol Technologies v. Lemelson used a 7-factor test in finding Lemelson’s patents unenforceable.
1. The overall delay between the filing of the application and the issuance of the claims;
2. The initial delay in presenting the claims to the patent office for the first time;
3. Lemelson’s original disclosures were made public in the 1960s, and the original patents based on those disclosures had expired by the early 1980s;
4. Before the asserted claims were filed, numerous articles and patents describing machine vision and bar code scanning had been published, and commercial products had been developed and marketed;
5. Lemelson was aware of the developments in the machine vision and bar code fields, but still delayed the issuance of patents asserting his claims;
6. Lemelson systematically extended the pendency of his applications by sitting on his rights, and sequentially filing one application at a time, so that he could maintain their pendency while waiting for viable commercial systems to be designed and marketed; and
7. Finally, after others had successfully developed and commercially exploited the technology, Lemelson drafted and prosecuted hundreds of new claims in the late 1980s and 1990s specifically worded to cover those commercial systems.
In addition, the Symbol court noted that widespread use of Lemelson’s technology prior to the suit “created adverse intervening private and public rights.”