Dr. J. J. R. Macleod. April 3rd. 1923.
cated to Dr. Clowes during his Toronto conferences, and in view of the
contents of Collip and Bests' specification, (of which he has a copy)
I fail to see how he can make claim 28.
To. 1 of Walden's process claims, covers broadly the puri-
fication of a product containing the anti-diabetic hormone by adjusting
the hydrogen ion concentration of water solution to the vicinity of
isolectric point. In my opinion this claim is broad enough in its
character to include not only the work done by Walden but also that
originally done by Collip and Best.
Nos. 2, 3, 4, 5, 6, 7, 8 and 9 of Walden's process claims are
also in the same category as Claim No. 1.
Nos. 10 and 11 of the process claims describe what Walden
has actually invented, viz, the purification of the final product
obtained by Banting, Best, and Collips' method.
Nos. 12 and 13 of the process claims are couched in language
which is broad enough to cover what was done by Collip and Best.
Nos. 14 and 15 of the process claims appear to be directed
to Walden' s method.
Nos. 17 to 23 of the process claims cover broadly the alter-
native of the work done by Collip and Best, that is, the PH value is
adjusted to precipitate the hormone, whereas, as I understand the case,
Collip and Best adjusted it to precipitate the protein.
If the Eli Lilly Company confines Walden's application to the
isolectric purification of the final product obtained by the Collip and
Best method, there can be no objection to what that company has done,
but if the Eli Lilly Company persists in its efforts to cover broadly