Freescale (formerly Motorola) was purchased by NXP (formerly Phillips) in 2015. Qualcomm is in the process of buying NXP, although apparently there's been some difficulty getting it past the European regulators. Now it sounds like Qualcomm is going to get swallowed up by Broadcom. That's going to be a huge company.
Last year, Microchip bought Atmel, ADI bought Linear Tech, ON Semiconductor bought Fairchild, and Renesas bought Intersil. The year before, Intel bought Altera.
Any bets on the last two semiconductor conglomerates standing? I'm thinking Intel vs. Samsung. I hope whoever swallows up ON Semiconductor rebrands to the Fairchild name - there's almost something poetic about a reverse-Fairchildren split.
EDIT: I should also point out that "Broadcom" isn't really Broadcom anymore - Avago Technologies purchased Broadcom last year and took on the Broadcom name for itself. Avago was previously the semiconductor division of Agilent which in turn was a spinoff of Hewlett-Packard. Avago traces its lineage back to the semiconductor division of HP which was formed way back in 1961.