The Nasdaq reached an all time high Tuesday thanks primarily to a strongly performing healthcare sector. The Nasdaq rose 0.7% to an all-time high of 5,403. The S&P 500 was up 0.3%, and the Dow Jones Industrial Average gained 0.2%. 

But what companies moved the needle most Tuesday? 

Meanwhile, Alexion (ALXN) - Get Report saw shares soar 7% Tuesday, hitting $126.44 apiece on news that the pharmaceutical company will be sued by shareholders for alleged securities law violations. 

Abbvie (ABBV) - Get Report also saw a boost Tuesday of 3.8% thanks to news that its drug for endometriosis, Elagolix could be effective in treating uterine fibroids. Abbvie shares hit $61.72 apiece Tuesday. 

Healthcare companies UnitedHealthcare Group (UNH) - Get Report and Aetna (AET)  were also up Tuesday, likely due to a combination of factors. 

UnitedHealthcare saw a boost of 3.7%, hitting $157.76 per share thanks to a better-than-expected outlook for fiscal year 2017. The company is hosting an investor day Tuesday, where more information on its future plans will likely emerge. 

Meanwhile, Aetna saw a boost of 3%, hitting $132.24 per share, on the opening of its court documents for its merger with Cigna (CI) - Get Report by the Department of Justice. Cigna saw a smaller boost of 2%, hitting $139.61 per share Tuesday. 

These stocks do not appear to be impacted negatively by President-elect Donald Trump's appointment of Rep. Tom Price (R-Mich.) to head of Health and Human Services. Little information is available on how he plans to run the department. 

Tuesday's biggest mover, however, saw share prices fall, thanks to a negative outlook in the generics sector.

Mallinckrodt plc (MNK) - Get Report saw shares fall around 8%, hitting $52.60 per share on a negative outlook for 2016. Despite this, the global pharmaceutical company reported better-than-expected earnings for the fourth quarter of 2016 Tuesday.