Piper Jaffray analyst James Fish says that while his firm is "big fans" of NGINX and what it could bring to F5 Networks (FFIV), the company lacks a controller, likely lowers medium-term estimates, could commoditize some of F5's base, and creates fear that F5's software-only solutions are struggling. This was a defensive acquisition, Fish tells investors in a research note. To the analyst's knowledge, F5 competitor Citrix Systems (CTXS) was already trying to acquire NGINX. F5 was likely leveraging NGINX within its coming software-only solution and couldn't let that fall to a direct competitor, says Fish. He's concerned around the "medium-term headwinds to estimates" but is encouraged by the long-term strategy of the deal. The analyst keeps an Underweight rating on F5 Networks with a $157 price target.