According to WSJ, Rockwell Collins (COL) approached by United Technologies Corporation (UTX)

Jet-engine manufacturer United Technologies Corp. (UTX) is weighing an acquisition of aviation-equipment supplier Rockwell Collins Inc., (COL) according to people familiar with the matter, in a deal that would potentially rank among the largest ever in the industry.

Update(s):

August 07, 2017: United Technologies Corp. (UTX) has made an approach to acquire Rockwell Collins Inc., (COL) but the two aerospace suppliers are still wrangling over the price of a takeover that would exceed $20 billion, said people familiar with the matter.

August 29, 2017: United Technologies Corp. (UTX) is nearing a deal to buy Rockwell Collins Inc. (COL) for more than $20 billion, a tie-up that would create one of the world’s biggest aircraft-equipment makers.

September 04, 2017: Industrial conglomerate United Technologies Corp. (UTX) reached a deal to buy airplane-parts maker Rockwell Collins Inc. (COL) for $23 billion, in the biggest aerospace deal in history.