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Medtronic's MiniMed split-off shows how separations can sidestep index funds

Medtronic swapped its entire 90% stake in MiniMed for its own shares in an exchange offer subscribed 5.4 times over. The structure changes who ends up holding the stock, and why.

· · 5 min read
Abstract illustration for: Medtronic's MiniMed split-off shows how separations can sidestep index funds
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Most corporate separations hand the new company to every shareholder of the parent, in proportion to what they already own. Medtronic chose a different route for its diabetes business. On October 14th the medical device group published the final results of its exchange offer for MiniMed Group, the insulin pump maker it floated on Nasdaq in March, and on October 15th it declared the separation complete. Holders tendered 297,521,390 Medtronic shares. Medtronic accepted 55,032,401 of them and handed over 252,813,348 MiniMed shares in return, its entire remaining interest. It now owns none of the company.

The headline figure is the demand. Medtronic said the offer was 5.4 times subscribed, which meant a final proration factor of 18.289133% for anyone who tendered more than an odd lot. Cleary Gottlieb, which advised on the transaction, called it the largest medtech split-off of all time. For individual investors the more interesting question is structural. A split-off decides who owns the new company in a way a spin-off does not, and that has consequences for index funds, for the share counts that drive index weights and for the trading in both stocks.

Spin-off versus split-off

In a conventional spin-off the parent distributes shares of the subsidiary pro rata. Every holder, including every index fund, wakes up owning the new stock whether it wants it or not. Corteva's separation of its seed business this month is the textbook case. S&P Dow Jones Indices added Vylor to the S&P 500 on October 1st, the day of the spin-off, in Corteva's place. Corteva itself was moved to the S&P MidCap 400 on October 6th, with the index provider stating that "post spin-off, Corteva will be more representative of the mid-cap market space." That single decision set off a chain lower down: Olin moved from the MidCap 400 to the SmallCap 600 to make room.

Funds that track the S&P 500 therefore kept Vylor but had to sell Corteva, while mid-cap trackers had to buy it. Such mechanical flows are what investors mean by the index effect: buying and selling driven by membership rules rather than by any view of a company's prospects.

A split-off works the other way round. Nobody receives the subsidiary automatically. Shareholders of the parent must choose to give up parent stock in exchange for subsidiary stock, and only those who opt in end up holding it. S&P Dow Jones Indices has long treated the two structures differently. When Weyerhaeuser split off its homebuilding arm into TRI Pointe Homes in 2014, the index provider stated that it "will not add the split-off company to any S&P 1500 index at the completion of the transaction." The new company has to earn its place later, like any other candidate.

What the terms told tenderers

Medtronic launched the offer on September 14th at a 7% discount: holders were expected to receive about $107.53 of MiniMed stock for every $100 of Medtronic shares tendered. There was a ceiling, however, of 4.5939 MiniMed shares per Medtronic share. On October 7th Medtronic disclosed that the pricing formula would have produced a ratio above that ceiling, so the cap applied. In plain terms, MiniMed's price had weakened enough relative to Medtronic's that tenderers would get less than the advertised premium.

They tendered anyway, in very large numbers. Preliminary results on October 12th showed 298,024,452 shares tendered, of which 93,311,404 came through notices of guaranteed delivery, a mechanism that lets holders tender shares they have not yet delivered. The final count was a little lower once those deliveries were settled. Because the offer was oversubscribed, Medtronic used its option to exchange all its remaining MiniMed stock rather than only the 225,361,295 shares in the base offer. Holders of fewer than 100 shares were exempt from proration and had their whole tender accepted, a small courtesy that favoured the smallest retail accounts.

A float that multiplied overnight

The most immediate effect falls on MiniMed's free float. When it priced its initial public offering on March 5th, selling 28m shares at $20.00 each, Medtronic retained about 90.03% of the company. For seven months the public could trade only the remaining sliver. Now essentially the whole share register sits with outside holders, many of whom acquired the stock not because they sought exposure to diabetes technology but because the exchange terms looked attractive.

Investors who hold a stock for arbitrage reasons tend not to hold it for long. On October 14th, as the final results came out, MiniMed traded at $17.39 in late morning, down 5.49% on the day and below its $20.00 offer price. A thin float turning into a wide one, with a large group of reluctant new owners, is a recipe for pressure on the price until the register settles.

That is also where index inclusion becomes a live question. Float-adjusted indices weight companies by the shares the public can actually trade. A company that was 90% owned by its parent carried little weight in such benchmarks. With the parent gone, MiniMed's investable size has jumped, which makes it a more natural candidate for broad indices once committees review it. Any addition would bring buyers that do not care about the price, the reverse of the flows that followed the exchange.

The other side of the trade

For Medtronic the transaction works much like a share buyback paid for in stock rather than cash. The 55,032,401 shares it accepted leave public hands without the company spending money, and the exchange is expected to be generally tax-free for Medtronic and participating holders under US federal income tax rules. Index funds that track the S&P 500 do not need to trade MiniMed at all: they held Medtronic before and they hold Medtronic now, simply a Medtronic with fewer shares outstanding. Chief executive Geoff Martha has framed the separation as a way to concentrate capital on Medtronic's cardiovascular, neuroscience and surgical businesses.

MiniMed, meanwhile, must now persuade a new shareholder base on the strength of its own results, without a parent whose stake once anchored the register.

Our view

The MiniMed exchange is a useful reminder that how a company is separated matters as much as whether it is separated. A spin-off pushes the new stock into every portfolio, including index funds that may have to sell it, which is why spin-offs so often trade poorly in their first weeks. A split-off avoids that forced selling but replaces it with something else: a register filled by holders who chose the stock for the terms rather than the business. Demand of 5.4 times the shares on offer says more about the attraction of a discount than about enthusiasm for insulin pumps.

What to watch now is whether index providers move to include MiniMed as its float is recognised, and how quickly the arbitrage holders rotate out. Until both happen, the price says little about what the business is worth. For Medtronic the measure is simpler: whether a smaller share count and a narrower focus show up in its earnings per share.

This article is for information only and is not investment advice.

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Filed under Investing. Written by Invest Times Editorial under our editorial standards. Commentary and analysis for information only, not investment advice.

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