On the same day a Texas craft brewery announced it is being acquired by industry giant MillerCoors, the group that represents the state's craft breweries said it's changing the definition of what it means to be a member.

The rule change, approved unanimously by the Texas Craft Brewers Guild board, would limit full membership to breweries with no ownership or controlling interest "by an alcoholic beverage industry member that does not otherwise qualify under this definition."

That would disqualify Revolver Brewing Co., which on Thursday said the craft and import division of MillerCoors is purchasing an ownership stake for an undisclosed amount. Revolver, based southwest of Fort Worth, could opt for a newly created associate membership, but it would no longer be able to vote on guild matters or participate in its legislative efforts, guild Executive Director Charles Vallhonrat said.

The rule change had been under discussion for about five months, and the timing of the announcements was coincidental, Vallhonrat said, adding that it is not meant to punish breweries that sell to a larger competitor. He said the change reinforces the guild's commitment to smaller, independently owned breweries that represent the fastest-growing segment of the beer industry but lack the resources of global conglomerates and often have different legal and regulatory goals and priorities.

The change also reflects the evolving U.S. beer landscape as more craft breweries are acquired by behemoths such as MillerCoors or Anheuser-BuschInBev. At least 14 such deals have been announced so far across the U.S., the Brewers Association reports.

"I think it's clear that the big brewers are interested in expanding their craft portfolios," said Brock Wagner, owner/founder of Houston's Saint Arnold Brewing Co. and a guild board member.

"It's a lot easier to buy a brand than to build one. I'm not surprised by the announcement."

Wagner said the new definition is meant to create "as bright a line as you can" even as investments by major brewers, private equity financial groups and international owners have blurred the lines that were fairly clear just a few years ago, before crafts began to eat into the domestic market share.

In 2015, for example, craft beer grew 13 percent by volume, even as the U.S. beer market overall shrunk 0.2 percent. Craft market share reached a record 12.2 percent.

Craft brewers brought in a little more than $1 of every $5 spent on beer last year, ringing up $22.3 billion in sales.

Vallhonrat said the Texas Craft Brewers Guild, whose membership has likewise ballooned to include more than 200 breweries and 80 to 90 suppliers and other allied trade groups, wanted to reiterate its commitment to breweries that do not have the backing of large corporations and yet "bring a lot of diversity to the industry."

Associate members can still participate in the guild's education, safety and marketing efforts.

Other definitions for being a guild member remain the same: A brewery must be licensed to operate in Texas, produce fewer than 2 million barrels annually and derive the majority of its beer "from traditional or innovative brewing ingredients and their fermentation." That does not include flavored malt beverages.

The only other Texas craft brewery affected by the rule change would be Independence Brewing Co. of Austin, Vallhonrat said.

California-based Lagunitas Brewing, which is half-owned by Heineken, this summer entered a strategic alliance with Independence.

Revolver founders Grant Wood, Rhett Keisler and Ronnie Keisler will remain in charge of their brewery after its acquisition, Wood said Thursday.

The most immediate change, he said, is that within the next two months the beer will begin distribution through wholesalers that represent MillerCoors. He said the deal also gives Revolver more resources to expand.

Revolver broke ground in Granbury in the spring of 2012 and has grown rapidly since selling its first keg that September.

Last year, it made 22,500 barrels, including five year-round beers and other occasional releases. It is in the midst of an expansion project that will double its production capacity.

In the Houston area, Revolver is best known for its Blood & Honey.