The Federal Circuit opinion quoted the language actually used in the application and that doomed it:
The present application is a continuation of allowed U.S. patent application Ser. No. 10/720,728, entitled “SYSTEM AND METHOD FOR DELIVERING REMOTELY STORED APPLICATIONS AND INFORMATION” filed on Nov. 24, 2003 now U.S. Pat. No. 7,502,838, the di[s]closure of which is hereby incorporated by reference in its entirety. CROSS REFERENCE TO RELATED DOCUMENTS Priority is herewith claimed under 35 U.S.C.§ 119(e) from copending Provisional Patent Application No. 60/153,917, filed Sep. 14, 1999, entitled “METHOD AND SYSTEM FOR DELIVERING APPLICATIONS IN CLIENT/SERVER ENVIRONMENT,” by Louis M. Franco et al. The disclosure of this Provisional Patent Application is incorporated by reference herein in its entirety.Dennis Crouch's Patently-O helpfully gives an example of the language that would have worked:
The present application is a continuation of allowed U.S. patent application Ser. No. 10/720,728, filed on Nov. 24, 2003 which has issued as U.S. Pat. No. 7,502,838, which is a continuation application U.S. application Ser. No. 09/599,382 filed Jun. 22, 2000, which has issued as U.S. Pat. No. 6,687,745 on Feb. 3, 2004, and which claims the benefit of Provisional Patent Application No. 60/153,917, filed Sep. 14, 1999.Professor Crouch notes that just reading the statute and regulations would lead one to believe that the priority claim should have been valid, but that the courts have interpreted the statute and regulations in a non-obvious way.
If you can't look at the two different priority claims above and know why one works and one doesn't, you need a patent lawyer.
This is far from the first time that companies using lawyers get caught in "gotchas" -- for example, Roche's predecessor left language out of an assignment agreement that cost it a patent worth tens or hundreds of millions of dollars. However, when an inventor uses a lawyer, there are two outs: First, pick a good lawyer and the mistakes are far less likely to happen. Second, part of the legal fee should cover malpractice insurance premiums, so as long as you confirm that your lawyer has appropriate coverage, if they get it wrong you aren't left high and dry (although it is important to note that few malpractice policies are going to cover very high dollar amount patent malpractice claims).
As long as you know what you're doing, there is no reason you can't draft your own specification, draft your own claims, even draft the whole application. However, whether you know what you're doing or not, there is a reason to have a good patent lawyer take a look at what you've drafted to make sure it threads all of the needles that patent applications need to thread.