What happened

Shares of Sonic Corporation (NASDAQ:SONC) were surging last month after the drive-in burger slinger agreed to sell itself to Inspire Brands, the parent of Arby's and Buffalo Wild Wings. As a result, the stock finished the month up 21%, according to data from S&P Global Market Intelligence.

As the chart below shows, the stock surged when the news came out on Sept. 25, accounting for nearly all of its gains last month as it reached an all-time high.

SONC Chart

SONC data by YCharts.

So what

Sonic agreed to be acquired by Inspire Brands for $1.57 billion, or $43.50 a share, representing a 19% premium from Sonic's closing price on Sept. 24 or a 21% premium from its 30-day moving average at the time. Including Sonic's debt, the deal is valued at $2.3 billion. 

A Sonic carhop smiling while delivering a meal on a tray.

Image source: Sonic.

Sonic CEO Cliff Hudson said, "This value-maximizing transaction validates the actions we have taken over the last year to grow traffic and improve sales while delivering differentiated offerings and superior guest service." Sonic had struggled through much of the restaurant recession, but the company recently returned to comparable sales growth as a preliminary earnings report on Sept. 11 momentarily boosted the stock. 

Inspire Brands CEO Paul Brown said, "Sonic is a highly differentiated brand and is an ideal fit for the Inspire family. We're excited to build on Sonic's momentum as we leverage our combined expertise and capabilities to better serve guests, further support team members and franchisees and drive long-term growth." 

Now what 

Sonic's acquisition follows a wave of consolidation in the restaurant as Popeye's was acquired by Restaurant Brands International, JAB Holdings acquired Panera Brand, and Inspire itself has been on the hunt for new brands as the company took over Buffalo Wild Wings just a year ago. The activity could lift share prices for other potential restaurant acquisitions.

As for Sonic, the deal seems likely to go through as negotiated, with shares now trading just a few cents below the $43.50 buyout price. The transaction is awaiting approval from Sonic shareholders and regulators, and is expected to close by the end of the year.

Jeremy Bowman has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.