US Markets ran to the upside on Merger Monday after Superbowl Sunday. Here are some of the after-hours most active:

1) Principal Financial Group Inc. (NYSE:PFG): Shares are down $1.50 or 4.45% for the provider of retirement savings, investment and insurance products and services after reporting that Q4 earnings rose 40%. Still, a 40% increase was not enough to top analyst expectations.

2) Herley Industries Inc. (NASDAQ:HRLY): Shares of the supplier of microwave technologies are up $2.55 or 15.69% after agreeing to be acquired by Kratos Defense & Security (NASDAQ:KTOS). The transaction is worth $270 million in cash.

3) Becton, Dickinson and Co. (NYSE:BDX): Shares of the global medical technology company are down $2.93 or 3.42% after-hours after reporting fiscal Q1 earnings that slowed by 0.1%. The company also announced the signing of an agreement to acquire Accuri Cytometers Inc.

4) Veeco Instruments Inc. (NASDAQ:VECO): Shares of the manufacturer of data storage and metal organic chemical vapor deposition systems used to make LEDs and solar panels are down $1.34 or 2.97%. Q4 earnings surged but guided lower for the current quarter.

5) Exide Technologies Inc. (NASDAQ:XIDE): Shares of the electrical energy sotrage company are up $1.76 or 16.84% after reporting fiscal Q3 earnings that grew over 300%. The company flew by analyst expectations and benefited from increased revenue and lower tax provisions.

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