Written by Laura Clift. (refs) point to "pycnogenol references" section.

All bioflavanoids are anti-oxidants (1,8,9) and may effect capillary
hyperpermeability (8,9), inflammations (3,8), and edemas (8). However, there
is no bioflavanoid deficiency condition, and they have "no accepted
preventive or therapeutic role in vascular purpura, hypertension,
degenerative vascular disease, rheumatic fever, arthritis, cancer, or any
other condition" (9). This was as of 1988; no mention of bioflavanoids is
made in the 1994 edition of this reference. Most pycnogenol studies and/or
claims come from the early 70's to mid 80's. Promising starts are never
followed up on. Most later studies seem negative (both pycnogenol and
bioflavanoids), especially about the oral route. With all but one study
performed in rodents, there is a very definite lack of information on how
this substance acts in humans and what possible side-effects it produces.

The sales pitch seems to be taken from the 1985 patent. Filing a medical
patent doesn't mean the substance is thoroughly studied and its applications
are determined. A patent is filed when preliminary studies look promising and
you try to come up with every possibly use for the compound, no matter how
far out in left field it may be. If you do not hold the patent for the
application, someone else could conceivably use your compound for that
application and owe you nothing or a very reduced royalty.

In short, patent claims have no medical significance.