PATENTS - Dependent claims and broadening

35 U.S.C. § 112(d) :

(d) Reference in Dependent Forms. — [A] claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.

Here's Dennis Crouch: 

In my mind, the Butamax claim structure does not fit within the structure authorized by §112(d) because the full effect of the “method” limitation is not included in the dependent composition claim. The result then, could be invalidity either as indefinite or for failure to comply with §112(d).  See Pfizer, Inc. v. Ranbaxy Laboratories Ltd., 457 F.3d 1284 (Fed. Cir. 2006) (claim invalid for failure to properly structure the dependent claim).

Strong comments at Patentlo-O on this recent Fed. Cir. case.