Your indexes are about to be rejiggered. You may want to alert your financial advisor.

S&P Global Ratings and MSCI Inc. announced their decision to shake up the Global Industry Classification Standard (GICS) structure last year, combining phone companies with internet and media stocks into a sector called “communication services.” The changes are set to hit in September.

But as the clock ticks closer, countless advisors apparently are still unaware of the nearing transformation.

Dave Haviland, managing partner of Beaumont Capital Management, a Needham, Massachusetts-based wealth manager, just finished a tour around the country, hitting Georgia, Alabama, Utah, Arizona, Louisiana and California to speak to advisors and clients both in person and at conferences. At the end of each conversation, he made a point to ask if anyone was aware of the sector reconstitution. And the disconcerting answer was an overwhelming, “No.”

“You would be absolutely blown away by how many people have never heard of it even today,” Haviland said by phone. “I asked after each one, ‘Has everyone heard of this?’ And it was just like deer in headlights.”

Haviland’s numbers are stark. In conversations with hundreds of advisors in more than 50 meetings, only one person knew of the sector shifts set for September, he said.

Some of the main changes involve removing roughly 18 media companies, including Netflix Inc. and Walt Disney Co., from the consumer discretionary category and adding them to the new communications service sector. Facebook Inc. and Google parent Alphabet Inc. will be moved as well, along with several other technology stocks, according to Beaumont Capital Management.

Index changes such as these aren’t common, happening once every few years, according to Spencer Mindlin, an analyst at Boston consulting firm Aite Group. And when they occur there can be consequences for funds that track the gauges.

Some exchange-traded fund firms are already making changes ahead of the moves. According to Mindlin, index providers will often work with large managers that are benchmarked to their products to smooth the process, but some can slip through the cracks.

“It’s impossible for a large index provider to keep track of all the portfolio managers tracking their index and try to ensure they are all consulted and notified in advance of changes,” he said. “It’s not uncommon for portfolio managers to discover that a change was made after the fact and have to ‘true up’ their holdings to match the index.”

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