Friday was a quiet end to a strong week for the stock market. Major benchmarks finished very close to the unchanged level, leaving the Dow, S&P 500, and Nasdaq Composite all either at or near record highs. Rising tensions on the geopolitical front as a result of the G7 summit in Sicily failed to translate into downward pressure on stocks, and most market participants appear to be optimistic about the prospects for continued outperformance from the U.S. economy. Even in a calm trading session, some stocks were quite strong, and Lions Gate Entertainment (NYSE:LGF-A) (NYSE:LGF-B), Nutanix (NASDAQ:NTNX), and AmTrust Financial Services (NASDAQ:AFSI) were among the best performers on the day. Below, we'll look more closely at these stocks to tell you why they did so well.

Lions Gate roars ahead

Shares of Lions Gate Entertainment were up 9% after the entertainment studio reported its fiscal fourth-quarter financial results late Thursday. Revenue soared by almost 60% because of the acquisition of premium cable channel operator Starz, and even when you run pro forma numbers based on year-ago results from the two companies separately, adjusted operating income climbed by more than a quarter over the past 12 months. The surprise success of blockbuster La La Land helped to drive much of the performance, but Lions Gate is even happier with the way that it has integrated Starz into its overall operational mix. With the television group posting record revenue, and plenty of promising opportunities ahead, Lions Gate hopes that this is just the beginning of a new upsurge that could take the content producer to the next level in the industry.

Lions Gate properties arranged in shape of constellation of Leo.

Image source: Lions Gate.

Nutanix climbs into the clouds

Nutanix stock rose 11.5% in the wake of the company's release of its fiscal third-quarter financial report. The enterprise cloud-computing specialist said that revenue jumped by two-thirds from year-ago levels, and although the company posted a wider net loss than it did in the third quarter of fiscal 2016, investors nevertheless were pleased that there wasn't even more red ink from Nutanix. CEO Dheeraj Pandey noted that the results "reflect our continued focus on the Global 2000 [list of large businesses] as well as a measurable improvement in the number of larger deals in the quarter, particularly in North America." With ongoing enterprise demand for cloud-computing services showing no signs of letting up, Nutanix should be able to use its positive momentum to capture future growth as well.

AmTrust Financial gets a vote of confidence

Finally, shares of AmTrust Financial Services finished higher by 12.5%. The beleaguered insurance company got an infusion of cash from family members of certain corporate insiders, including CEO Barry Zyskind and board member George Karfunkel. The private placement involved the sale of 24.1 million shares of stock at $12.45 per share, bringing in $300 million. Shareholders took the move as a vote of confidence in the company's future prospects, despite controversy surrounding the company and its practices. Today's jump makes the Zyskind and Karfunkel families big winners, giving them more than $36 million in profits in a single day on their newest purchases.

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