Even though a Supreme Court ruling forcing Amazon to collect state sales tax hit the online retailer's shares Thursday, one analyst says investors shouldn't give up on the stock.

Amazon's shares fell as much as 2.4 percent in the week of the decision, but regained much of their footing as the day went on. Shares were off 1 percent heading into the final hour of trading.

CFRA analyst Tuna Amobi said the company's already huge footprint in the online commerce space will allow it to retain share and likely fare better than many of its smaller competitors.

The firm kept its "buy" rating on the stock.

"On face value, the ruling might raise the specter of potential negative implications for AMZN, which recently accounted for about 44% of the U.S. e-commerce market and an even more dominant 70% of overall e-commerce growth," Amobi wrote in a research note. "Still, we see a relatively limited exposure for AMZN, which already collects a sizable amount of sales taxes across many states where it qualifies as taxable due to its sufficiently large physical presence."

Amobi also noted that the ruling was only "mildly surprising" even though it overturned a 26-year-old precedent that prohibited states from collecting sales taxes from companies that had no physical presence in their locales.

Consumers now are expected to face additional costs for online purchases. Amobi anticipated, though, that Amazon would not "cede a meaningful portion of its market share" to smaller brick-and-mortar competitors.

Indeed, other companies fared much worse after the ruling.

Overstock slumped 7 percent in late-day trading, eBay dropped 3 percent and Etsy was down about 1.8 percent.

Amazon shares are up more than 48 percent year to date and 73 percent over the past 12 months.