I haven't seen anyone list this point, however given Todd have indicated they won't participate in the buyback suggests they will be in breach of Section 606 of the Corporations Act 2001 (Cth)
http://www.takeovers.gov.au/content/DisplayDoc.aspx?doc=panel_process/summary_of_takeover_provisions_in_australia.htm
20% acquisition limit:
Section 606 prohibits the acquisition of a relevant interest in voting shares if, because of that transaction, a person's voting power in the company:
(i) increases from under 20% to over 20% or
(ii) increases from a starting point that is above 20% and below 90%.
Exceptions to the prohibition in s606, include:
- an acquisition that results from an acceptance of an offer under a takeover bid (item 1 of s611)
- an acquisition approved by a resolution of the company in which the acquisition is made (item 7 of s611)
- acquisitions of no more than 3% in every 6 months (the 3% "creep" exception in item 9 of s611)
- an acquisition that results from a rights issue (item 10 of s611)
- a downstream acquisition resulting from an acquisition of relevant interests in another listed entity (item 14 of s611) and
- acquisitions resulting from a scheme of arrangement (item 17 of s611).