The Affordable Care Act, also known as Obamacare, was seen as a positive catalyst for some health insurance providers and the sector in general.

Those that are not fans of Obamacare, and there are plenty, are not apt to give the sweeping but controversial legislation much credit for the success of health care equities and exchange traded funds. In the essence of civil political discourse, let’s just say Obamacare has played a part in, but is far from the only reason the Health Care Select Sector SPDR (NYSEArca: XLV) has surged almost 90% in the past three years. [Health Care Delivering Even as Other Sectors Struggle]

Health insurance providers have delivered higher returns for shareholders with Obamacare seen as a primary catalyst. However, some of the marquee names in that sub sector look technically vulnerable and Obamacare is a fundamental reason why.

“As news comes to light about the demands placed on insurance companies, and especially the changing deadlines of its implementation, uncertainty has gotten crippling. Even one of the strongest stocks since the law’s passage, UnitedHealth (NYSE: UNH), has not made any net progress since July,” reports Michael Kahn for Barron’s.

Fortunately for XLV investors, that ETF only allocates 15.5% of its weight to insurance and services providers, well behind the 65% combined weight to pharmaceuticals and biotech names. The ETF vulnerable to declines in health insurance providers is the iShares U.S. Healthcare Providers ETF (NYSEArca: IHF).

IHF, which allocates 13.5% to Dow component UnitedHealth, has had its day in the Obamacare sun, soaring almost 37% last year. The charts of some IHF’s largest holdings indicate some profit-taking could be afoot. [Obamacare Could Boost This ETF]