We wanted to provide some more information and rationale behind S4x24 ticket limits for all organizations except for asset owners.

First, we have found great value in having attendees from ICS security product and consulting vendors, ICS vendors, national labs and other non-asset owner attendees. Quite frankly many of the attendees from these organizations bring new, bleeding edge ideas to S4 and help move the Create The Future mission forward. These attendees have often left the asset owner world because they want to push some pioneering effort. Staking their career and spending their time on this.

I could provide numerous examples from previous S4. The ICS product and consulting attendees have shown some of the most innovative cyber-physical hacks; they were very early showing OT detection and OT SBOM and OT DPI and a bunch of product approaches that didn’t succeed; and they introduced a focus on consequence and other ideas.

Since we don’t have an exhibit floor at S4 and the S4 target attendee is an advanced ICS security pro, the vendor’s tend to send some of their top technical talent rather than the trade show and sales teams. Of course some of the trade show and sales come, but they typically are not very successful at their mission of collecting a large number of leads. In fact, we tell the sponsors that if their metric is quantitative lead collection, then S4 is probably not going to a good event for them even though it is one of the largest events.

All this is a long way of getting to: S4’s goal is not to maximize asset owner attendence. The mission is to help Create The Future of OT & ICS Security, and the non-asset owner categories are essential to achieving this.

Why Limits On All Except Asset Owners?

The first reason is we reached our capacity of 1,100 attendees this year at S4x23 and had to turn away ~100 who wanted a ticket. Funny/sad story is a few people didn’t believe the sell out and traveled to Miami Beach to plead to buy a ticket onsite. We had to say no because 1,100 wasn’t an artificial limit. The space could not handle more.

S4 has averaged a 30% AGR the last three years. So we will likely sell out earlier and have to say no to more. As of this post on October 18th, we are at ticket #639.

Second, we were seeing large vendors sending 30+ people. This is 3% of the attendees. We were seeing small vendors sending most of their team, 10+ or 1% of the attendees. It’s less clear that any organization sending this many people is the best way to meet the Create The Future mission. Could getting half as many of the best people from an organization, in S4’s constrained size, better help meet the mission? We think yes.

Also, asset owners and vendors asked for more asset owners to attend. We believe they are underrepresented at ~25% of attendees. (Although they tend to be the early adopters, willing to try new things, and have strong opinions, perfect for S4). We’d like to see them represent somewhere between 33% and 40% of the attendees.

First week results indicate we may want to put limits on number of attendees from asset owner companies as well (a couple of asset owner contingents are 20+ attendees). Still at this point there is no cap on number of attendees from an asset owner company.


We will reconsider the limits and mix when we get up to 900 tickets. Where should we focus the remaining 200 tickets. Not sure when this will happen.

We will also look at the number of attendees and the attendee mix at the start of 2024, about two months before the event. If it doesn’t look like asset owners will fill the remaining tickets we will loosen up the ticket limits.