Pakistan’s top court on Friday found that the party of imprisoned former Prime Minister Imran Khan was improperly denied at least 20 seats reserved parliament, in a significant blow to the country’s fragile governing coalition.

The ruling by the Supreme Court was hailed by Khan’s Pakistan Tehreek-e-Insaf party, which was previously excluded from a system that gives parties extra seats reserved for women and minorities in the National Assembly or lower house of the parliament.

Though the verdict is a major political win for Khan, it will not put his party in a position to oust the government of Prime Minister Shehbaz Sharif, who came into power following a Feb. 8 election that Khan allies say was rigged.

Pakistan’s constitution reserves 60 seats for women and 10 for minorities, doling them out to political parties in proportion to the number of seats they win in elections.

Pakistan’s Election Commission blocked the PTI from participating as a party, saying it had not properly chosen its candidates through internal elections and forcing its candidates to run as independents. The Supreme Court overruled that decision, saying that a political party could not be deprived of its reserved seats.

Sharif was elected premier by the National Assembly in March, with 201 votes in a 336-member house. The PTI is expected to get at least 20 more seats after the ruling, adding to the 86 it currently holds.

Khan is currently in prison in the garrison city of Rawalpindi after convictions in multiple cases.