The bears took a pretty good swipe at the bulls today … early on. By the time the closing bell rang though, the bulls pushed back, and then some. The S&P 500 ended the day at 2,364.87, up 0.08%, and testing the waters of higher highs again.

Not every name sidestepped some punishment, however. STMicroelectronics NV (ADR) (NYSE:STM), International Game Technology Ordinary Shares (NYSE:IGT) and America Movil SAB de CV (ADR) (NYSE:AMX) were on the ropes all day long, and ended the day mostly KO’d.

Here’s what investors need to know about each.

America Movil SAB de CV (ADR) (AMX)

Antitrust concerns aren’t strictly a U.S. phenomenon. Most countries are reasonably strict when it comes to too much of one market being controlled by too few players. Just ask investors of Mexican telecom company America Movil SAB de CV, who watched their AMX shares tank to the tune of 5.3% on Thursday after the country’s telecom regulators ruled it must split up its fixed-line division and allow competitors to use its lines.

America Movil is primarily owned and controlled by billionaire investor Carlos Slim, who has enjoyed the company’s dominance of the space in the Mexican market. The country’s Federal Telecommunications Institute is not only going to require a split-up proposal from America Movil within 65 days, it’s also putting into place several other antitrust-oriented rules that pose a threat to AMX by weakening the company’s strong, monopolistic hold.

International Game Technology Ordinary Shares (IGT)

The casino-gaming and lottery kiosk maker may have topped earnings estimates for its recently-completed Q4, but it still wasn’t enough to satisfy IGT shareholders.

For its most recently completed quarter, IGT earned an operating profit of 88 cents per share on revenue $1.32 billion. The top line just missed expectations of $1.33 billion, but the bottom line handily topped estimates for a profit of only 47 cents per share of IGT. Few other metrics and measures were palatable though. Revenue was still down on a year-over-year basis, and CapEx is expected to grow by $100 million this year, eating into margins.

Concerned investors send IGT shares 15.3% lower for the day.

STMicroelectronics NV (ADR) (STM)

Last but not least, the 2.4% setback shares of semiconductor company STMicroelectronics suffered on Thursday may not be a massive loss, but it was a dramatic one considering who else is involved in the news.

On Thursday, rumors surfaced that STMicroelectronics may not be able to deliver the sensors for the next series of the Apple Inc. (NASDAQ:AAPL) iPhone, which is expected to launch in September. According to sources familiar with the matter, the delay could be on the order of several months.

It’s not entirely clear, if true, if STMicroelectronics is to blame, or if a recent redesign from Apple is the root cause. Regardless, the mere prospect of disappointing the venerable Apple — which can make or break a supplier — was enough to send STM shareholders into something of a panic.

As of this writing, James Brumley did not hold a position in any of the aforementioned securities.