Wyoming and 10 other states’ claims that giant investment companies conspired to drive coal production down and drive prices up — increasing people’s energy costs — are at least plausible enough to keep a lawsuit alive, a judge has ruled. Wyoming filed suit in the U.S. District Court of Eastern Texas in late November against Blackrock Inc., State Street Corp. and Vanguard Group Inc. Texas Attorney General Ken Paxton led the litigation. Alabama, Arkansas, Indiana, Iowa, Kansas, Missouri, Montana, Nebraska, West Virginia and Wyoming also signed the complaint. The states allege the three massive investment companies acquired substantial stockholdings in...