Medtronic launched an exchange offer on September 14 covering 80.1% of MiniMed's outstanding common stock. Shareholders who tender Medtronic stock get roughly $107.53 in MiniMed shares for every $100 they hand in, a 7 percent discount. The offer runs through October 9.

MiniMed listed on Nasdaq as MMED in March and raised about $538 million net. Medtronic held roughly 90 percent afterward, more than 252.8 million shares. The stock traded at $21.50 on the day of the announcement, up about 18 percent since the IPO. If the offer is oversubscribed, Medtronic can move the rest of its stake.

CEO Geoff Martha said the separation lets Medtronic put capital behind its cardiovascular, neuroscience and surgical portfolios. MiniMed CEO Que Dallara said it "gives us complete autonomy over our capital allocation, our product roadmap, and our speed."

For anyone building in diabetes, the practical change is budget authority. A standalone MiniMed sets its own spend on the patch pump and insulin-calculation algorithm it has already filed, without those programs competing internally against cardiac ablation.