The Tiniest Monthly Filing in Australia Tells You Everything About ResMed's New Share-Buying Plan

On August 5, ResMed filed a 300-word appendix with the Australian Securities Exchange saying, in effect: we have 591,346,650 of these paper certificates outstanding, down 2.7 million from last month. This document - called an Appendix 4A - is the most widely ignored financial filing in the country. It tells you how many CHESS Depositary Interests (CDIs) are on issue for a company whose actual shares trade in New York.

Last month's filing was the mirror image: CDIs surged by 22.8 million. The press called it a surge. Nobody asked which direction the money was actually going.

The weird thing is that the CDI number is a perfect backward-facing read on what ResMed is doing with its capital, and right now the company is in the middle of a major shift. ResMed agreed on June 30 to sell its MatrixCare software business to private equity firm Frazier Healthcare Partners for $490 million in cash. The company said the proceeds would go into an accelerated share repurchase. Then the CDIs shrank.

So let's work through the plumbing, because it matters more than it looks like.

ResMed is incorporated in Delaware and trades its common stock on the NYSE under the ticker RMD. It also has a "foreign-exempt" listing on the ASX, which is how US companies get a secondary presence in Australia without registering as foreign issuers. The ASX listing doesn't trade actual shares - it trades CDIs. Each CDI represents one-tenth of a share. You need 10 CDIs to make one share.

CDIs are basically a receipt for a fractional share that sits in a custodial wrapper. Australian investors can trade them in Australian dollars, during Sydney trading hours, through their normal broker. Underneath, a depository holds the actual NY-listed shares. When someone buys CDIs on the ASX, the depository converts NYSE shares into CDIs. When someone sells CDIs, they convert back. The total number of CDIs on issue is a live reflection of how many Australian investors want local exposure versus how many shares exist in New York.

This is a standard dual-listing structure. It's used by a number of US health and tech firms with Australian ties. What makes ResMed interesting is the scale of its CDI float - roughly 59.1 million shares' worth, at the 10:1 ratio - and what happens to that float when the company starts buying back shares.

Here's the mechanism. When ResMed buys back shares, it does so on the NYSE. Shares get retired. The total pool of common stock shrinks. But some of the CDIs on the ASX still point to shares that don't exist anymore, or are about to be cancelled. So the CDI balance has to adjust downward. Either CDIs get cancelled as they convert back into shares that get retired, or fewer CDIs are created because there are fewer underlying shares to deposit.

The June filing showed CDIs rising by 22.8 million. The July filing shows them falling by 2.7 million. What's between those two months is the MatrixCare deal and the announcement of the accelerated buyback.

You can also see the other moving parts in the June filing. The RMDAB securities - the NYSE-side equivalent of the CDI pool, representing common stock held outside the ASX wrapper - fell by 24.6 million. The RMDAA common stock count fell by 2.5 million. The filing explicitly attributes the decline to transfers between CDIs and common stock, stock option and RSU exercises, employee stock purchase plan activity, and share repurchases. That last item is the one doing the heavy lifting.

The simplest model is this: every dollar ResMed spends on buybacks reduces the share count, and that reduction eventually shows up in the CDI plumbing. The monthly Appendix 4A is a lagging indicator of how much share destruction the company is executing.

Why does any of this matter? Because the size and direction of ResMed's capital returns is changing, and the CDI balance is the least visible but most transparent window into it.

In the first half of fiscal 2026, ResMed repurchased $325 million of stock, up from $125 million the prior year. In Q3 alone, it returned $262 million through dividends and buybacks combined. Now it has $490 million of fresh cash coming from the MatrixCare sale - and it intends to put that into an accelerated share repurchase. An ASR is a deal with an investment bank where the company pays upfront and receives a fixed number of shares immediately, with the remaining shares delivered at the end of a holding period. It locks in a price and accelerates the buyback on the share-count side, even though the cash leaves the balance sheet today.

The ASR is the part that makes the CDI plumbing especially interesting. Because the bank delivers shares quickly and the company retires them, the share count compresses faster than a slow drip-fed buyback would. The CDI balance should reflect that compression more sharply than you'd expect from a normal repurchase program.

For Australian investors, the practical consequence is that the CDI float is shrinking - which means the ASX-listed instrument is getting less dilutable over time, even as it carries the same proportional claim on the underlying company. Fewer CDIs outstanding, fewer shares outstanding, the same business underneath. That's not a trading signal, exactly. It's a structural change in the ownership base.

The other context worth noting is why ResMed is doing all of this. The MatrixCare sale is a $490 million cash event for a business that generates roughly $220 million in revenue and $55 million in non-GAAP operating profit - a sale multiple of about 9x operating profit, which is respectable but not euphoric. ResMed is also absorbing the Noctrix acquisition, which adds roughly $30 million in revenue but trims non-GAAP EPS by about $0.20. The company is shedding one software business and adding a neuromodulation hardware business, while simultaneously returning the MatrixCare proceeds to shareholders.

All of this happens against a stock that is down roughly 20% over the past year, weighed down by concerns that GLP-1 weight-loss drugs could reduce demand for sleep apnea treatment. Third-quarter revenue still rose 11% year-over-year to $1.43 billion, and non-GAAP EPS climbed 21% to $2.86. The buyback program is management's way of saying the stock is cheaper than the business justifies.

Whether that's right or wrong is a separate argument. The CDI filing doesn't adjudicate the valuation case. It just tells you how the plumbing works when management is committed to buying back its own stock.

The structural implication is simpler: ResMed is turning a divestment into permanent share reduction, and the ASX's most boring monthly filing is the only place where you can see the share count actually shrink, one certificate at a time.