From Wikipedia, the free encyclopedia
Submarine patent is an informal term for a patent first published and granted long after the initial application was filed. In analogy to a submarine, its presence is unknown to the public; it stays under water, i.e., unpublished, for long periods, then emerges, i.e., granted and published, and surprises the relevant market. This practice was possible previously under the United States patent law, and is now not practical with present patent filings since the U.S. signed the TRIPS agreement of the WTO: since 1995, patent terms (20 years in the U.S.) are measured from the original filing or priority date, and not the date of issuance. A few potential submarine patents may result from pre-1995 filings that have yet to be granted and may remain unpublished until issuance. Submarine patents are considered by some, including the US Federal Courts , as a procedural lache (a delay in enforcing one's rights, which may cause the rights to be lost).
Under Article 93 EPC, a European patent application shall be published as soon as possible after the expiry of eighteen months after the date of filing or, if priority has been claimed, as from the date of priority.  Consequently, the key submarine patent strategy of delaying publication of a patent application for several years is not possible.
Also, it is not admissible to amend the claims of a European patent application to include subject matter that extends beyond the content of the application as originally filed.  In Europe, this requirement is interpreted strictly (to protect third parties' interests ) to mean that information that is not directly and unambiguously derivable from the application as originally filed may not be added subsequently. This reduces the possibility of a granted patent having significantly different or broader scope than the patent application as published. Claim broadening, in particular, is subject to particularly careful examination under European practice. 
A further limitation on amending patent applications following publication is that amended claims may not relate to unsearched subject-matter which does not combine with the originally claimed invention or group of inventions to form a single general inventive concept.  Only the claims as originally filed in a European patent application are subject to a search and this rule further reduces the possibility of a European patent having significantly different or broader scope than the patent application as published. An exception to this rule is that new claims may be filed on bringing an international (PCT) application into the European phase  which may be the subject of a new search.
Divisional applications may be filed under Article 76 EPC at any time while an earlier European patent application is pending.  Divisional applications are still published as soon as possible after 18 months from the priority or filing date of the parent application to make the public aware of the contents of the divisional as early as possible.
The claims of a divisional application may differ from the claims of the parent application as originally filed, potentially causing an unexpected monopoly to be claimed, so that, as the Enlarged Board of Appeal put it,
- "third parties need to be aware that while any divisional application is still pending, any of its content as filed may yet be the subject of patent claims either in the divisional application itself, or in further divisional applications." 
Nevertheless, Article 76(1) EPC requires that a divisional application may only be filed in respect of subject matter which does not extend beyond the content of the parent application as originally filed. The failure to meet this requirement may be remedied by amendment after filing, as confirmed by Enlarged Board of Appeal decisions G 1/05 and G 1/06 of June 2007. This language mirrors Article 123(2) EPC and therefore offers the same protection to third parties that a divisional application may not claim subject matter which was not directly and unambiguously derivable from the parent application as originally filed. In this respect, European law provides no equivalent to the controversional continuation-in-part practice of the USPTO.
 United States
In the past, when the life of a U.S. patent was 17 years from the date it was granted, submarine patents could issue decades after the initial filing date. Therefore, an applicant for a U.S. patent could benefit by delaying the issuance, and thus expiration date, of a patent through the simple, but relatively costly expedient of filing a succession of continuation applications. Some submarine patents emerged as much as 40 years after the date of filing of the corresponding application.  During the extended prosecution period the claims of the patent could be tweaked to more closely match whatever technology or products had become the industry standard.
Currently, the majority of U.S. patent applications are published within 18 months after the filing date. However, the applicant can explicitly certify that they do not intend to file a corresponding patent outside the U.S. at the time they file the patent, and keep the application secret. The applicant can change their mind within the first year, but the application is then published. For continuation applications which claim priority to a previously filed application, the publication is six months after the new filing date. The changes to U.S. patent law that introduced publication at 18 months also changed the duration of the patent to 20 years from the filing date of the earliest patent application in any chain of continuation patent applications. As a result there is little benefit in postponing the grant of the patent. The enforceable life of the patent can no longer be shifted into the period when a technology has become more widely adopted, and the patent applicant must give up the chance of foreign patent protection if he is to maintain patent secrecy beyond the 18 month period. In a recent report the National Academy of Sciences has recommended that "in all cases, applications should be published during patent examinations". 
 Famous submarine patent owners
At a minimum, Lemelson's delay in securing the asserted claims amounts to culpable neglect as he ignored the duty to claim his invention properly.... If the defense of prosecution laches does not apply under the totality of circumstances presented here, the Court can envision very few circumstances under which it could.... In sum, Lemelson's delay in securing the asserted patent claims is unexplained and unreasonable.
The patents at issue in this case are; U.S. Patent 4,338,626; 4,511,918; 4,969,038; 4,979,029; 4,984,073; 5,023,714; 5,067,012; 5,119,190; 5,119,205; 5,128,753; 5,144,421; 5,249,045; 5,283,641 and 5,351,078.
 Notes and references
- ^ See Famous submarine patent owners below
- ^ Nevertheless, if the European patent application has been granted before the expiry of 18 months from the filing or priority date, the application will be published simultaneously with the publication of the European patent.
- ^ Article 123(2) EPC
- ^ Guidelines for Examination in the EPO, C VI 5.3.1
- ^ Guidelines for Examination in the EPO, C VI 5.3.10
- ^ Rule 137(4) EPC, previously Rule 86(4) EPC 1973.
- ^ Rule 161 EPC, previously Rule 109 EPC 1973.
- ^ Rule 36(1) EPC, previously Rule 25(1) EPC 1973.
- ^ Decision G 1/05 of the Enlarged Board of Appeal of the EPO, Reasons 9.2.
- ^ "Of course, there are a few original patent applications that take decades to issue as well, but this is due to secrecy restrictions, interferences, Board, district court or Federal Circuit appeals. See, e.g., U.S. Patent No. 5,132,080 (an original application was filed November 28, 1944 and the patent was not permitted to issue until July 21, 1992 due to secrecy restrictions); U.S. Patent No. 6,097,812 (filed July 25, 1933 and delayed due to secrecy until August 1, 2000); U.S. Patent No. 6,130,946 (filed October 23, 1936 and delayed due to secrecy until October 10, 2000). Pursuant to 35 U.S.C. §181, the Commissioner of the PTO must withhold the granting of any patent "[w]henever publication or disclosure ... by the grant of a patent on an invention in which the Government has a property interest might, in the opinion of the head of the interested Government agency, be detrimental to the national security." Id. Although §181 only permits the Commissioner to delay patent issuance for up to one year, the secrecy can be renewed for an unlimited number of one year periods if it is in the interest of national security." in Mark A. Lemley, Kimberly A. Moore, Ending Abuse of Patent Continuations, Boalt Working Papers in Public Law (University of California, Berkeley), Year 2003, Paper 20, page 9, footnote 27.
- ^ The National Academies, "Changes Needed to Improve Operation of U.S. Patent System". Retrieved on February 17, 2006.
- ^ Dead Patents Walking, IEEE Spectrum Online. Consulted on February 29, 2008.
- ^ Susan Hansen, Breaking the (Bar) Code, IP Law & Business, March 2004 (pdf, 500k)
- ^ United States Court of Appeals for the Federal Circuit, 04-1451, Symbol Technologies, Inc. et al v. Lemelson Medical, Education & Research Foundation, LP, September 9, 2005 p.13 (pdf format)
- ^ and additional order for that November 16, 2005 (pdf format)