Huge takeovers in the oil and pharmaceutical sectors helped lift the S&P 500 to a record Monday, while the Dow fell shy of a new mark.
At the closing bell, the S&P 500 stood at 2,041.19, up 1.37 points (0.07 percent).
The Dow gained 12.94 (0.07 percent) to 17,647.68, narrowly missing a record, while the Nasdaq fell 17.54 (0.37 percent) to 4,671.00.
Oil-services giant Halliburton announced $34.6 billion takeover of rival Baker Hughes, while Actavis unveiled a $66 billion acquisition of Botox-maker Allergan.
Those deals helped offset the drag from Japan's fall back into recession with an 0.4 percent contraction in the third quarter.