This full text of the notification SKV M 2020:1, which is published on the Swedish Tax Agency's website (www4.skatteverket.se/rattsligvagledning/381557.html?date=2020-01-13), states that:

Of the original acquisition cost of the ordinary shares in Moberg Pharma, 60 percent represents the redemption shares and 40 percent the remaining ordinary shares.

Tax rules for redemption
When a shareholder redeems shares in a company, the shareholder is deemed to have sold the shares. As a result, a capital gain is calculated. In the calculation, the shareholder may deduct the portion of the original acquisition cost represented by the redeemed shares.

Alternatively, the standard approach may be used for shares that are publicly listed. In the standard approach, the acquisition cost may be calculated as 20 percent of the consideration received for redeemed or sold redemption shares.

Since the redemption shares are traded for a period of time, they are considered to be publicly listed. 

Example
If the acquisition cost of an ordinary share in Moberg Pharma immediately before the split is SEK 40 in this example, (0.6 x 40 =) SEK 24 represents the redemption share. The remaining ordinary share is then assigned an acquisition cost of (40 - 24 =) SEK 16.

If the redemption share is sold or redeemed for SEK 46.50, a capital gain arises of (46.50 - 24 =) SEK 22.50