A lot of it was broken down into base elements. I know I've seen a propaganda film the Soviets were quite proud of that featured German helmets being fed into a machine that would press them into cooking pots. Unfortunately Youtube isn't being helpful in finding it again.

If it were in working order or pretty damn close, it could potentially be put to use. France had plenty of Panthers in near-working condition- thanks largely to the fact that the Germans could lose upwards of half of them through no fault besides mechanical failures and battle wear meaning that they just needed new parts to run again- that they would, ironically, end up using longer than the Germans.

A fair amount of equipment found it's way to the middle east where it would serve in conflicts there, which is how you find something like this.

Some production facilities would retain the rights to build Nazi designs. The Spaniards kept some German aircraft designs made by the Nazis in service well after the Nazis ceased to be- many WW2 movies ended up being filmed in Spain for this exact reason. The Czechs built the Hetzer post-war for domestic use, and exported about 150 to Switzerland.

Small arms had a habit of finding their way all over the world. American soldiers in Iraq during the 00's found a weapon stash that included old left overs from Nazi Germany. MP40's and Kar 98k's also found their way into the hands of the Viet Kong during the Vietnam conflict, and various African revolutions. Norway's Home Guard was using the MP38 in some capacity till it was replaced by the MP5 in 1990 or so, and the Home Guard also made use of the Kar 98k till the 70's. The MP44 actually stayed in service in Eastern Germany until it could be replaced with the AK-47, and their police force would employ it till as late as the 60's.

In a rather bizarre twist, the British made MP28's- dubbed the Lanchester SMG- after Dunkirk at the behest of the RAF which would see use after WW2.

was it ever given to private companies?

What exactly do you mean here?

The surrender agreement in 1945 called for the handover of all war material to local Allied military forces and the immediate status of the war material was determined by the victorious Allies. Some of this war material was designated for immediate use and testing. Captain Eric Brown, one of the RN's chief test pilots and fluent in German, ranged throughout Germany looking for flyable examples of state of the art Luftwaffe aircraft that could be returned to the UK and put through their paces. The Type XXI and Type XIII submarines elicited considerable interest from all of the Allied powers and they became war booty, as did the experimental Walter high test peroxide submarine, which entered into British service as HMS Meteor Meteorite. The French looked to German war material as a means to supplement their own rearmament in the postwar period. The Soviets tended to keep war material that was in working condition to parse out to its allies in Eastern Europe (or allow their allies to retain this material, such as Czechoslovakia). This was a way to ease the defense burden on the Soviet occupation in the immediate postwar years while keeping its allies in a subordinate position. But inertia and expediency also played a role as the war material was already there and the Red Army had no need for it.

But the above examples were the exceptions, not the rule. The overwhelming bulk of German war material was scrapped in the immediate postwar years, There was little interest in maintaining or even demilitarizing this equipment as much of it was already in bad shape by April 1945. Aircraft boneyards often had the planes stripped of valuable materials and the planes were simply melted down or thrown into a landfill. The same applied to tanks and other heavy equipment; salvageable engines might be removed and some parts used in reconstruction. The barrel of La Gleize's Tiger II tank is actually a Panther barrel that was recovered from a Belgian barn where it was used as a support beam. The American zone had a structured recycling plan, Gesellschaft zur Erfassung von Rüstungsgut m.b.H. (GER)- later retitled Staatliche Erfassungsgesellschaft für öffentliches Gut m. b. H. (STEG), in which German intermediaries worked to recondition or salvage war material that could be put to civilian use. GER/STEG warehouses worked on items like uniforms and boots and other state materials, including surplus US material. The organization's portfolio also tasked it with separating out components useful to peaceful purposes and handing over other materials for destruction. Corruption within GER/STEG was pretty common as its officials as the amount of state-owned material at its disposal was quite vast while the time of the postwar years was one of great dearth. GER/STEG's role in reconstruction is one that is pretty understudied and there is an forthcoming article in War & Society about the agency.

Munitions posed a particular problem for the occupation. Some German munitions could simply be immediately repurposed for the destruction of obstacles and fortifications. But that still left a massive quantity of explosives, including chemical munitions that were not used during the war, but stockpiled by Germany. The British zone authorities tended to dump mass quantities of munitions into the ocean. The other Allies followed suit by burying them in landfills or dumping in lakes.Although news media reports on unexploded munitions typically stress that the weapons were the byproduct of wartime use, the sheer scale and haphazard nature of postwar disposal does not rule out these explosives were the result of peacetime negligence. The decay of these munitions, especially the chemical weapons, has caused some alarm in environmental quarters, as this Spiegel article outlines.