Pfizer refused to put a ring on it – on Allergan, that is. That’s right: the Pfizer and Allergan merger is off.

The two large pharmaceutical companies had been planning a $150 billion wedding, to be celebrated by a honeymoon in Ireland, Allergan’s home turf. The biggest wedding present promised to be a “tax inversion” for Pfizer, since its headquarters would be moved away from New York to overseas.

Tax Inversion Plan Foiled at the Altar

Tax inversions are a polite way of referring to a newly-merged company’s intent to dodge US taxes by moving their headquarters out of the country – even if it’s only on paper. And that’s exactly what the Pfizer and Allergan merger would result in, saving Pfizer about $35 billion in tax dollars. Pfizer had already announced that it would move its headquarters to Dublin after the buyout.

Unfortunately for the star-crossed pair of companies, a couple of uninvited guests crashed the party: President Obama and the US Congress, who this month changed US tax law and broke up the romance. The Treasury Department announced changes to the corporate tax codes to close the tax inversion loophole.

Corporate Nuptials Nipped In the Bud

Of course, prior to walking away from the altar, Pfizer did protest a bit too much that the move to the Emerald Isle had absolutely, positively, 100% nothing to do with avoiding its fair share of taxes in the US. When the Pfizer and Allergan merger was announced in February, Pfizer insisted that the deal was “not structured to move jobs out of the United States, where we conduct the majority of our research.”

However, just like any other jealous groom, Pfizer changed its tune when the breakup recently hit the news, claiming that the deal had been scuttled because of an “Adverse Tax Law Change” clause in the merger agreement. Pfizer will pay Allergan $150 million in transaction expenses for breaking off the engagement.

No Hard Feelings – Except Towards US Government

The jilted bride, Allergan, was ever-so-miffed at the wedding’s cancellation and claimed that it had been targeted by the US government, which had been intent all along on spoiling its marital bliss. According to CNBC, Allergan’s CEO Brent Saunders said, “It really looked like [the US government] did a very fine job of constructing a rule here – a temporary rule – to stop this deal.”

Although most would say all’s fair in love and war, Saunders further complained that, “For the rules to be changed after the game has started to be played is a bit un-American.” One assumes he wasn’t at his Dublin office at the time of his comment.