About the Authors

  • The Authors and Contributors of "Patent Docs" are patent attorneys and agents, many of whom hold doctorates in a diverse array of disciplines.
2018 Juristant Badge - MBHB_165
Juristat #4 Overall Rank

E-mail Newsletter

  • Enter your e-mail address below to receive the "Patent Docs" e-mail newsletter.

Contact the Docs


  • "Patent Docs" does not contain any legal advice whatsoever. This weblog is for informational purposes only, and its publication does not create an attorney-client relationship. In addition, nothing on "Patent Docs" constitutes a solicitation for business. This weblog is intended primarily for other attorneys. Moreover, "Patent Docs" is the personal weblog of the Authors; it is not edited by the Authors' employers or clients and, as such, no part of this weblog may be so attributed. All posts on "Patent Docs" should be double-checked for their accuracy and current applicability.
Juristat #8 Overall Rank


« Sen. Tillis Sends Letter to President Regarding Next USPTO Director | Main | Senators Request USPTO to Provide Information on Subject Matter Eligibility »

March 08, 2021


Call this a "random" observation: one thing about the claim seemed a little odd to me. It starts by claiming a conjugate of FVIII and "one or more biocompatible polymers"—i.e., there potentially are multiple polymers. However, all the remaining language in the claim uses the singular when talking about a polymer. It is "the" polymer; the polymer "comprises"; and the polymer "is" attached at the B-domain. That makes it a little confusing. Does it mean that actually just one PEG is ever attached, or can there be instances of attaching more than one polymer? If the latter, are they all the same—i.e., all PEG—or are they actually different types of the claimed polymers?

Dear Hard:

Keeping in mind that indefinite articles like "a" or "an" are usually construed to mean "one or more" (unless there is a reason not to), and "comprising" means "what is recited and other things," we have "an" isolated polypeptide conjugate comprising "a" functional factor VIII polypeptide. The "biocompatible polymer(s)" are recited as "one or more," so that there can be more than one of these. The rest of the claim is limited to functional factor VIII polypeptide comprising a particular amino acid sequence (SEQ ID NO: 4) or an allelic variant thereof, and is further limited to having "a" (one or more) B-domain. Then the biocompatible polymer comprises polyalkylene oxide (PEG being a specific embodiment of this broader genus) that is covalently attached to the functional factor VIII polypeptide at the B-domain. This latter is what is necessary to distinguish over the prior art, where PEGylation of Factor VIII was, according to the opinion, randomly distributed. So the claim contemplates possibly more than one PEGylation provided that 1) at least one is in the B domain; and 2) it isn't randomly distributed in the Factor VIII protein.

How many and where PEGylation occurs is bounded by the prior art, the prosecution history, and the teachings in the specification. Baxalta tried to get the claim limited to conjugation at cysteine residues (because their conjugation was at lysine residue(s), I suppose) and the court wouldn't limit the claims to these embodiments.

Thanks for the comment

The comments to this entry are closed.

May 2024

Sun Mon Tue Wed Thu Fri Sat
      1 2 3 4
5 6 7 8 9 10 11
12 13 14 15 16 17 18
19 20 21 22 23 24 25
26 27 28 29 30 31