Okay, a bit of a history lesson here.
In the early 1980s Big West needs extra funding to do Macross and Tatsunoko is the one that they chose to go with. Among the agreements is that Tatsunoko can give distribution rights.
In 1983/1984 these rights are bought by Harmony Gold to distribute Macross outside of Japan. There is wording in this that is said to include derivatives based on Macross in the contract.
At about the same timeframe rights are sold to FASA who want to use designs in their Battletech Mechwarrior game.
1984 HG decides to shelve releasing Macross directly to home video and push it to go on television. Needing 65 episodes minimum for a weekly run Carl Macek is brought in and Southern Cross and Mospeada are packaged and altered to fit one timeline, Robotech.
1985 Robotech airs.
1990s Many of Harmony Gold's staff for their entertainment division are poached by Saban Entertainment. The majority of them go to work on the original Power Rangers. This period is known as "Nobody minding the store". It is during this timeframe that Macross II is brought over by US Renditions and Macross Plus by Manga Entertainment with no challenge.
Early to mid 1990s. FASA sues Playmates over the Robotech toys that were going back into circulation under the Exo Squad banner. FASA loses the challenge when Harmony Gold is brought in and is found out that the one who sold them their contract in the 1980s never had the rights to it to begin with. Details here:
www.youtube.com/watch?v=4WRy_n7gpDM&t=6m41s
Late 1990s, circa 98-99. New staff at HG is hired specifically for Robotech and HG begins to go over their rights.
Toycom is given a C&D order and cannot bring their Macross toys over legally without getting the go ahead from them first. Word goes back to Big West over legalities.
Big West sues Tatsunoko. Please note that Harmony Gold has nothing to do with this lawsuit other than bringing up the question of how much leeway Tatsunoko had over the rights for licensing. Wording seems to be broad.
It has also been speculated that HG has to go after these breeches within a certain timeframe or they lose the rights to do so.
There have been counter-suits since. The only thing gleamed from this is that Big West has the rights to the artwork from what I remember. When this will be resolved we do not know.
Harmony Gold has no issue with more Macross products abroad, but due to the legality that they believe they have under what was granted to them by Tatsunoko they want their logo on whatever release comes out. That's pretty much it, and in the past more Macross product was to come, but BW pulled the plug on them.
At Comic Con 2003 (which I attended) during the Robotech Panel they announced that Tokyopop was to release the manga Macross 7 Trash and even had it on Robotech.com. Big West pulled the plug on that as it was around the time of the legal battle in Japan.
ADV was going to attempt to license Macross Zero and Big West told them to go to HG. HG said yes and Big West balked (as likely did not want to give HG any legitimacy that could hurt them in the courts). This is talked about in Chris Meadow's podcast Space Station Liberty when he had Tommy Yune on as a guest:
http://recordings.talkshoe.com/TS-8042.mp3
It's about halfway through when it comes up.
Macross DYRL is a fucking mess legal wise, even before Tatsunoko vs Big West started. They do not know how that international dub came out but it'll be the only one that comes out at this time. Not even HG is sure who owns what portions other than when someone tries to license it everyone will come out of the woodwork. Oddly enough, they found out Tatsunoko had the legality for merchandise so they snapped that up (which is why you see HG backed DYRL merch out). When they were asked by fans why didn't anyone else get those rights HG said that Tatsunoko told them no one else asked.
As for Macross 7 the two big issues (not including the third which is Tatsunoko vs Big West) which kept licensors away before that particular mess was that they had to pay for two licenses, as the animation and music were being shopped separately, and from what I remember Robert Woodhead of Animeigo complaining about at the Macross panel at AX '99 was that the music rights costs exceeded that of the animation for interested parties in the US. Due to that unless there was a guarantee that M7 would make it big in the US it was a property that was not likely to be touched.