Pulgasari is probably North Korea's most famous contribution to cinema internationally. This Godzilla homage has been overshadowed by the real life story of kidnapped South Korean director Shin Sang-ok and his ex wife Choi Eun-hee and how they used the promotion for Pulgasari as an opportunity to escape in Austria.
I reviewed the movie a long time ago . It's worth a watch if you're a Kaiju fan. There are better big monster movies but there are also much worse and its setting and themes are quite unique.
North Korea does have copyright, this may be surprising given how their country is heavily associated with industrial scale piracy and espionage. The rest of the so-called communist world also passed copyright laws and eventually took steps to conform to international standards including the Bern convention. North Korea took longer than most, its statute defining copyright was passed in 2001 with a period fifty years after the death of principle authors. They updated this policy in 2006 and I can't find anything in there about the legislation being retroactive. This means that much of its cultural and artisitc output was technically public domain immediately, though the isolation of the country and its limited economic activity outside of the Soviet bloc and the People's Republic of China meant that much of its output was not available. Pulgasari was an exception as it received a big push internationally.
This combination of factors is why it's relatively easy to find subbed copies of the film floating around the internet and home printed dvds available in places like ebay. I believe that Pulgasari is one of the few films you could argue that lack of a robust copyright system did hurt its owners ability to make money. The film was a flop abroad but has since become a cult hit, but what money has been made from this resurgence in interest has been to South Korean and Asian small scale distributors and not the North Korea state.
North Korea's ex-dear leader Kim Jong Il had been trying for years to build an internationally respected and financially viable cinema industry, and while it may sound silly the movie with a rubber monster costume was a key part of his offensive. In a way it's a good thing it failed and most of the money went into other pockets. The North Korean state would use those funds to secure itself and the film and television industry as tools for domestic control and foreign influence. They had already kidnapped South Korean film makers and the Japanese cast and crew of Pulgasari including Godzilla actor Kenpachiro Satsuma were lied to about shutting locations and brought to North Korea under false pretences.
That's another issue with intellectual property rights, they're value neutral so it's perfectly acceptable that the owners are enriched and can use IP as a tool to win hearts and minds. In theory IP is for the benefit of struggling artists, but often the reality is that the beneficiaries are corporations with a strained relationship with ethics, or despotic governments.