Highmore was placed on waivers by the Islanders on Tuesday, per Stefen Rosner of NHL.com.
Highmore produced two goals and four helpers over 41 regular-season appearances with the Senators last year, and he also notched 10 points in 23 games with AHL Belleville. Highmore will report to AHL Bridgeport if another team does not claim him on the waiver wire.
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