It depends on the type of pre-market engagement the authority is undertaking and the justifications for this. Ultimately, any pre-market engagement activity must not have the effect of distorting competition and must not result in a violation of the principles of non-discrimination and transparency (see Regulation 40 of the Public Contracts Regulations 2015).
In terms of illustrative examples:
If an authority is conducting a general presentation to the supplier market about a forthcoming opportunity, it may be difficult to justify restricting the number of attendees. This is because the authority could conduct the presentation via an online platform, or if it wished to run an “in-person” event, it could restrict the number of representatives from each organisation attending in this capacity, while at the same time providing a recording of the session online for those who have not been able to secure an “in-person” place.
If an authority wished to organise more in-depth “one-to-one” sessions, then it seems more likely that restricting the number of organisations participating in this capacity would appear more reasonable. Ultimately, the authority is not obliged to comply with the principle of equal treatment during pre-market engagement (see reference to Regulation 40 above), however if an authority did not accept one to one meetings with all interested suppliers, this could of course be construed negatively and the authority would need to exercise care in respect of allegations of non-discrimination (e.g. if the authority reserved the right to only offer one to one sessions with UK-based organisations, unless this could be objectively justified). A potential way of managing such perception could be to make clear that if the authority receives a high demand for one to one sessions, it will distribute such appointments on the basis of selecting suppliers representing cross-sections of the market in order to gauge as broad an understanding of the market as possible. For example, a proportionate representation of SMEs vs organisations who specialise in ‘X’ and other organisations who perhaps specialise more in ‘Y’ and so on and so forth.