There's been a lot of consolidation in the rental car market, and Hertz Global (NYSE:HTZ) wants to make sure that it's the eater and not the eaten. Hertz is embracing a poison pill plan today after observing "unusual and substantial" trading of company stock.

Hertz stock is moving higher on the news. But it's not that the market's excited about Hertz making it harder for an unsolicited buyer to take control of the auto rental giant. The stock is moving higher because it seems as if someone may be interested in acquiring Hertz in the first place.

Hertz adopting a shareholder rights proposal comes during the same holiday-shortened trading week in which Netflix (NASDAQ:NFLX) has chosen to let its poison pill lapse.

Netflix introduced its plan 13 months ago when its stock was trading in the double digits. The stock had fallen out of favor, and the still-growing video service didn't want to be taken over on the cheap. It may have been appetizing at the time for tech titans or cable and satellite television providers to take a chance on the leading premium streaming platform. If a buyout was in the offing, CEO Reed Hastings wanted to make sure that it was on Netflix's terms.

Netflix's plan was supposed to be in place for three years, but it seems as if the coast is clear now. The stock has more than quadrupled in price, but it's not just a matter of a potential suitor having to pay four times as much for Netflix as it would have 13 months ago. Now that the stock is rolling, investors are spoiled to the point that they would expect a much larger premium than they would have settled for when the stock seemed rudderless at $75 and the poison pill was adopted.

Unlike Netflix's three-year plan, Hertz is only putting its shareholder rights plan into play for a year. It will have a clearer picture by then of who -- if anyone -- wants to take the wheel. 

Either way, Hertz is open to swallowing a poison pill just as Netflix is spitting one out.