The recently rebuilt sentence detector (currently in trunk and the 3.1.0 branch) is sometimes taking the apostrophe as a sentence break where the ctakes-3.0.0-incubating model didn’t.
The training data used for the recently rebuilt model only contains only 7 lines that end with an apostrophe (single quote) followed immediately by a newline
It has >100K occurrences of 's
It has >175K occurrences of the ' character in all.
The place I noticed this is in testfakenote.txt.xml in ctakes-regression-test.
The word "Broca's" used to have a ContractionToken but since a sentence is now ending on the apostrophe, the apostrophe is getting annotated as a PunctuationToken.
See more in the thread started at
including examples that split correctly and incorrectly.