By Philip Blenkinsop BRUSSELS (Reuters) -The European Union launched a legal challenge against China at the World Trade Organization on Friday, arguing that Chinese courts were preventing European companies from protecting their telecom technology patents. The European Commission, which filed the challenge on behalf of the EU’s 27 members, said EU companies were being deterred from going to a foreign court to safeguard their standard-essential patents (SEPs). The Commission has also consulted the United States and Japan, whose standard-essential patent holders face similar challenges and which…