Australian tax data

Demerger cost base splits from ATO class rulings

When an ASX company demerges, the ATO publishes a class ruling that says how to split your cost base between the shares you had and the ones you received. You get that split with each demerger, along with share splits and consolidations.

Start for free API reference

GET /v1/corporate-actions 1 credit per instrument

curl "https://api.quova.io/v1/corporate-actions?symbols=ASX:BHP,ASX:ACE&from=2015-01-01&to=2023-12-31" \
  -H "Authorization: Bearer $QUOVA_API_KEY"

Response

200 OK 2 credits

{
  "data": [
    {
      "symbol": "ASX:BHP",
      "instrument": {
        "id": "ins_34VMvft6kZEXThtzFGcAL",
        "symbol": "ASX:BHP",
        "name": "BHP Group Ltd",
        "type": "equity",
        "mic": "XASX",
        "currency": "AUD",
        "country": "AU"
      },
      "asOf": "2015-05-24T00:00:00Z",
      "actions": [
        {
          "type": "demerger",
          "status": "completed",
          "effectiveDate": "2015-05-24",
          "announcedDate": "2014-08-19",
          "demerger": {
            "childName": "South32",
            "child": "ASX:S32",
            "ratio": 1,
            "au": {
              "costBaseApportionmentPct": 7.1
            }
          }
        }
      ]
    },
    {
      "symbol": "ASX:ACE",
      "instrument": {
        "id": "ins_34VN9N07Go23ZrlLllFc9",
        "symbol": "ASX:ACE",
        "name": "ACUSENSUS LIMITED.",
        "type": "equity",
        "mic": "XASX",
        "currency": "AUD",
        "country": "AU"
      },
      "asOf": "2023-07-27T00:00:00Z",
      "actions": [
        {
          "type": "split",
          "status": "completed",
          "effectiveDate": "2023-07-27",
          "announcedDate": "2023-06-23",
          "split": {
            "old": 1,
            "new": 5
          }
        }
      ]
    }
  ],
  "errors": [],
  "meta": {
    "credits": 2,
    "requestId": "req_34VoxwVB3DzylkFGYbJQh"
  }
}

How the split works

A demerger doesn't add to your cost base. The ATO divides what you paid between the parent and the new company, often in proportion to their market values in the first days of trading. costBaseApportionmentPct is the part that moves to the demerged company.

BHP's demerger of South32 in May 2015 shows how it works. Class ruling CR 2015/40 puts 7.1% of the cost base on South32 and leaves 92.9% with BHP, based on the volume weighted average prices of both over the five trading days after 18 May 2015. If you'd paid $10,000 for your BHP shares, $710 of that became the cost base of your South32 shares and $9,290 stayed with BHP.

Demergers covered

Each percentage is the one the ATO's class ruling sets for that demerger. A few examples, with the ruling to check them against:

Demerger	Year	Ruling	To the new company
BHP to South32	2015	CR 2015/40	7.1%
Woolworths to Endeavour Group	2021	CR 2021/50	14.19%
Tabcorp to The Lottery Corporation	2022	CR 2022/58	82.24%

For some older demergers, like Tabcorp's 2011 demerger of Echo Entertainment, the ATO published the split apart from the ruling, and the field is null for now. Demergers are covered for companies listed on the ASX.

Splits and consolidations

The same endpoint returns share splits and consolidations with the old and new share counts. ASX coverage is complete from December 2019. Earlier ASX splits and those on other exchanges go back to 1980, and are most complete for US listings.

Questions

Why is there no costBaseApportionmentPct?

Either the ATO hasn't published its ruling yet, or it's an older demerger where the ATO published the split separately. We don't fill in a number the ATO hasn't set.

Does the split apply to my shares?

It's the split the ATO's class ruling sets for the shareholders it describes. If your situation is unusual, like holding through a trust or not being an Australian resident, read the ruling itself.

Do you give the number of new shares per share held?

Yes, ratio is the new shares you get for each share held, as the ATO's ruling states it. It's null when the ruling doesn't give one.

What about takeovers and returns of capital?

The endpoint has types for them, but we don't cover them yet, so they don't appear. Some returns of capital show up in the dividends endpoint with a type of return_of_capital.

What does it cost?

1 credit per instrument. It's included in every plan, Free included, and in the trial. Anything that comes back as an error isn't billed.

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