From Ballot Access News:

Rocky De La Fuente this year is being kept off the November ballot in three states because of state laws on “sore losers” and prior affiliation with a major party. See the underneath posts on Alabama and Arkansas, where no court challenges have been filed. De La Fuente does have a pending case in Pennsylvania on the same issues, although the Pennsylvania case does not involve a state that has contradicted itself in the past over whether presidential primaries are covered by sore loser laws. The Pennsylvania case is De La Fuente v Cortes, m.d., 1:16cv-1696. It has a status conference on October 31, 2016, far too late to restore De La Fuente to the ballot, but a vehicle for resolving the issue.

Article II of the U.S. Constitution makes it utterly clear that the candidates in November, for states that choose to allow popular voting for president, are the candidates for presidential elector. In the early years of the 20th century, this was obvious to everyone, because general election ballots listed all the candidates for presidential elector, and voters could vote for individual candidates for elector. Thus voters could even split their tickets, and express support for more than a single presidential candidate.

Another issue is whether the U.S. Supreme Court decision U.S. Term Limits v Thornton, from 1995, means that sore loser laws for federal office are unconstitutional for candidates for president and congress.

From Ballotpedia:

American businessman and political activist. He is running for President of the United States on the Reform Party and American Delta Party tickets for 2016. He competed unsuccessfully for the 2016 Democratic nomination for President and the Democratic nomination in Florida’s 2016 election for United States Senator.