Most supplement labels cannot tell you which ocean. This one can tell you which sound, how often the water is tested, and how long the mussel sat in it.

Everything in the bottle begins in the Marlborough Sounds, at the top of New Zealand's South Island. Not a region or a coastline. One specific body of water, chosen for what is not around it.
There is no agriculture on it. No commercial development, no housing, no runoff. Government authorities test the water every week, and MacLab, the company that farms and processes it, tests it again anyway.
It starts as spat, mussel spawn roughly the size of a grain of salt, gathered from wild seaweed at the top of the North Island.
The spat is set onto ropes 120 metres long, hung from floating buoys. Twice during its life it is stripped off and reseeded into a fresh biodegradable stocking that dissolves on its own within a few weeks. Reseeding is about space: thinned out, the mussels are not competing with each other for what the water carries.
Eighteen months later they are about four inches long, which is the size worth harvesting. All mussel farming in New Zealand is licensed and controlled by the Ministry of Fisheries. The mussels are never fed. Everything they are made of came out of that water.
Harvest bags hold up to a ton of wet mussels. They go straight into refrigerated trucks for the two hour run to the processing plant at Nelson, which has been running since 1999 and is audited by the New Zealand Food Safety Authority: the facility, the hygiene and the paperwork alike.
Inside, the mussels are crushed shell and all, with no heat applied at any point. Heat is the problem here, because it destroys the marine lipids the whole process exists to capture.
What is left is separated by centrifuge, stabilised under a patented process, then freeze dried under full vacuum for twenty-two hours. The dried result is milled to a fine powder and sealed into nitrogen-filled foil bags so it cannot oxidise.
A crew spends eight hours a day cleaning that plant. Someone independent of them checks the work before the next run starts.
The powder travels to an extraction facility outside Nelson. The oil is drawn out using carbon dioxide under pressure rather than a chemical solvent, at low temperature, under patent licence.
From there it ships in drums to be formulated and bottled in Fort Lauderdale, and then it comes here.
Eighteen months, a licensed farm, a plant that stops when the weather turns, and an extraction process that refuses to use a solvent. None of that is quick and none of it is cheap. It is also more than most supplement labels can tell you about anything in the bottle.
Ask your pharmacist whether it suits you. They set the price, so they have no reason to oversell you.