Although the NSW Strata Schemes Management Act is big on rules and regulations for what should be done before and during meetings, it’s pretty light on penalties for not doing so. The significant issue here is if decisions can be rescinded if owners were not told about the meeting. And that comes down to a simple consideration: would the outcome of the vote have changed if the person excluded had been able to vote.
Section 25 of the Act says the Tribunal can nullify a vote on these grounds, however…
(2) The Tribunal must not make the order unless the Tribunal is satisfied that the resolution would not have been passed but for the fact that the applicant for the order—
(a) was improperly denied a vote on the motion for the resolution, or
(b) was not given due notice of the item of business in relation to which the resolution was passed.
It goes on to say that you must have applied for mediation within 28 days of the meeting that you are disputing, so best get your skates on if you are thinking of objecting.