Over 500 of Los Angeles’ medical marijuana shops have closed in the last two years, and it’s not for lack of clientele.

When city officials agreed to crack down on the shops under Proposition D, only about 140 of the city’s estimated 700 shops were expected to meet the newly imposed standards. The requirements include things like being registered under past city ordinances and maintaining a certain distance between your dispensary and public parks and schools.

According to the Los Angeles Times, City Attorney Mike Feuer says neighborhood complaints over illegal marijuana stores have been on the decline.

Nonetheless, city officials have no official way to know how many dispensaries are still operating, making the crackdown critically termed a murky game of whack-a-mole. By enforcing the guidelines, however, city officials hope to force anyone considering opening a new shop to think hard — though residents and supporters of Prop D have voiced complaints that as one shop closes, another is open within the week.

In a 2013 Next City feature on Los Angeles dispensaries and Prop D, UCLA Public Policy professor Mark Kleiman argued that “There’s no such thing as ‘good medical marijuana policy’ at a city level.”

Indeed, Philadelphia opted for pot decriminalization late last year and, by many accounts, the move has been successful. California, statewide, has also made some measures to decriminalize marijuana with reduced fines and penalties.