Eric S. Marmurek is CFO & VP at Ribbon Communications Inc. (RBBN). They have made 1 open-market trade across 1 company since 2019, most recently 2026-05-15.
CIK 0001720721
Unrated. We grade insiders only on stock they chose to buy on the open market. Grants, option exercises and vesting say nothing about timing, so they don't count — which is why someone can file often and still have no grade. It isn't a bad sign: unrated buys beat every graded tier below A.
0 open-market purchases, against 1 sale. Too few scored purchases to measure a record yet.
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.