On January 9th an Iranian born man (Mozaffar Khazaee) who was an engineer and an American citizen, was arrested after he was caught trying to ship tech manuals for the F-35 back to Iran. The F-35 material was hidden among household goods being shipped from the U.S. to Iran. Khazaee was arrested as he tried to board a flight from the U.S. to Iran (via Germany) and was charged with espionage. Khazaee was 59 and had worked for several American defense contractors.
Iran often attempts to use Iranians living in overseas (especially in the United States) for smuggling and espionage, particularly if they have access to material Iran wants. In this case Iran did not particularly need F-35 technology, but countries it does business with (like Russia and China) do and the F-35 material could be traded for all sorts of things Iran needed and Russia or China could supply.
The Chinese already have a growing collection of F-35 material. In 2012 British aircraft manufacturer BAE confirmed that Chinese hackers gained access to classified BAE aircraft design files in 2009. This included data on the American F-35 fighter, which BAE is helping to develop and build. BAE was working on the F-35 fuselage, portions of the wings and tail, the fuel system, crew escape system, life support and integration of British components for the British F-35s. All or much of the date on these items was apparently taken by the Chinese hackers.
Meanwhile the war on Iranian arms smuggling has been intensifying since September 11, 2001. Most countries cooperate, but not all. While Turkey has been getting cozy with Iran, the Turks still enforce international trade sanctions against Iran. But as Turkey encourages its companies to do more business with Iran, there are more opportunities to smuggle forbidden goods to assist Iranian nuclear weapons and ballistic missile projects. Iran takes advantage of this whenever possible.
Germany was once a favorite place for Iran to buy equipment for their ballistic missile and nuclear weapons programs but after 2005 the Germans began cracking down. For example, in 2008, a German citizen was prosecuted for running a weapons related smuggling operation. The defendant shipped 16 tons of high-grade graphite, used for making rocket nozzles, to Iran in 2005-7. The defendant mislabeled the graphite as low-grade, which was legal to sell to Iran. Another ten tons of the high-grade graphite was caught by Turkish customs officials. Germany adopted stricter export rules for Iran in 2007 and promptly began seeking out and prosecuting those who ignored the ban. This did not stop the Iranians from using Germany as a source of forbidden goods. In response, Germany has been prosecuting people for exporting special metals and manufacturing equipment needed for ballistic missile warheads. All this slows down the Iranians but has not stopped them.
Ever since the U.S. embargo was imposed in 1979 (after Iran broke diplomatic protocol by seizing the American embassy), Iran has sought, with some success, to offer big money to smugglers who can beat the embargo and get needed industrial and military equipment. This is a risky business, and American and European prisons are full of Iranians, and other nationals, who tried and failed to procure forbidden goods. The smuggling operations are currently under more scrutiny, and attack, because of Iran's growing nuclear weapons program. But the Iranians simply offer more money and more smugglers step up to keep the goodies coming.