CUNNING WORKAROUNDS

Naval architects have an entire toolkit of tricks at their disposal. Retractable canopies let a yacht offer shade and shelter when at anchor, then fold away before the surveyor arrives, so that on paper the space is open to the sky and doesn't count. Hull shaping and tumblehome (where the topsides curve inward as they rise) can reduce enclosed volume higher up the vessel without visibly shrinking the footprint from the water. None of this is illegal. It is simply a rational response to an irrational threshold. Goodhart would be nodding in resigned approval.

GOING OVER 500

What often goes unsaid is that the 500GT line is not the terrifying administrative cliff-edge it's made out to be. Yes, the ISM and ISPS Codes apply. Yes, you'll need a proper Safety Management System, more formal crew certification, and more detailed technical surveys. But let's have some perspective here. The incremental administrative burden of proper safety management documentation is not going to break the bank. Leave that to the crew salary and fuel invoices.

The fact is that exceeding 500 gross tonnage can actually help an owner. While the various international conventions are largely avoided when below this figure, they often frame the industry and legal standards to which owners must meet—especially as employers of crew. Taking the Maritime Labour Convention for example, isn't red tape for its own sake. It requires written employment agreements, defined hours of rest and decent accommodation. The standards required in respect of larger vessels are often still the same standards which courts will expect owners of all sizes of superyacht to meet—even if compliance doesn’t require certification. Seeing this as mere paperwork to be avoided can, ironically, leave an owner more exposed, not less.

A LITTLE-KNOWN LOOPHOLE

This loophole is rarely exploited. The 1969 rules (Regulation 1(3) of Annex I of the International Tonnage Convention 1969 to be precise) allows for vessels with genuinely novel features of their design to have those novel aspects treated differently – and potentially excluded from GT calculations – where applying the letter of the law to something unprecedented would be unreasonable or impractical. Meanwhile, Article 11 of the same convention makes it clear that a tonnage certificate issued by one ship registry must be accepted at face value by all other convention countries. No re-measuring. No dockside arguments.

And just as haute couture showcases brave new designs on the catwalk, so superyachts often feature novel features. Extraordinary glass atria. Shape-shifting beach clubs. Transforming decks. Flourishes that may never have existed afloat before. Yet this provision appears to have gone almost entirely unexercised.

VOLUME OF EVIDENCE

Gross tonnage was never meant to be a game. It was meant to be a simple, honest description of how much cargo a vessel can carry, so that sensible, proportionate rules could follow. Instead, it has led to some of the most brilliant engineering minds available spending their careers creating workaround designs. That's not a criticism. It's rather glorious. Goodhart told us it would happen, and the superyacht industry has proved him right.