Vol. I, No. 49 · San Francisco — Monday, October 12, 2026 · Price: two weeks’ notice

BY MAXINE DOLAN, CITY DESK

Barbarossa Lounge, a cocktail bar at 714 Montgomery Street, held two of San Francisco’s five longest guest lists in September, eight days apart. On September 17, the last day of the Dreamforce conference, 744 people had signed up for an unofficial closing party there by the morning of the event. The list was full. By the morning of September 25, 709 had signed up for the bar’s own farewell that night. After nearly 11 years, Barbarossa was closing.

Between those two parties sits the whole month. San Francisco listed 1,403 public gatherings in September by this paper’s count, about 47 a day, and 308 of them put AI, agents or a model in the title. That is 22 percent of the listings. Those 308 events held 52 of the 100 longest guest lists and 21,410 of the 53,352 registrations the city could see, or 40 percent. For anyone hosting something else, that is the competition: a free weeknight room, often with a sponsor paying for the drinks.

The month had a shape. Wednesday was the city’s night, with 324 listings, then Thursday with 285; Monday had the fewest, 96. Of the 1,403 gatherings, 868 began between 5 and 9 p.m. The busiest single day was Thursday, September 17, with 86 listings as Dreamforce wound down. The quietest was Labor Day, with 10. Nearly nine in ten were free: 1,218.

The AI share grew as the month went on. It was 16 percent of listings in the first week and 26 percent in the last nine days. A typical AI event’s list ran to 73 names, against 19 for everything else. The AI events were also fuller. Of the 308, 83 showed “sold out” on the last read before doors, 27 percent. Everything else filled at 19 percent.

The longest list of the month was not a crowd. The Thought Experiment Lab, a discussion night at The Commons in Hayes Valley, showed 1,787 registered on September 2. Its own page said most of those names had carried over from earlier events in the series, and that it expected not much more than 30 people. The same host’s Short Story Symposium on September 30 carried the same note. This paper left both out of every ranking. The case is a fair warning for the rest: a registration is a click, not a body in a chair.

The biggest rooms were also not the most reliable ones. By format, the best fill rate in the city belonged to book clubs and reading nights. Eleven of 32 were full before doors, 34 percent. Gatherings whose titles named no format at all filled at 15 percent. The back page has what else separated the rooms that filled.

Confidence is high on the listing counts. Every public listing in the city was read nightly through the month. It is medium on the AI share, because a title can miss it: the 942-name Rows & Columns Summit was a database conference and does not count. The count covers public pages on one platform, Luma. Concerts, ticketed shows, invitations sent by text and private dinners are not in it.

Barbarossa’s last party had DJs upstairs, live performances downstairs and nothing to demo. Seven hundred and nine people signed up anyway.

Of 1,403 public gatherings, 292 were full before doors. The ones that filled had more than one host, two or more weeks of notice, and a subject. Charging money did not hurt them.

BY HAZEL WONG, NUMBERS DESK

Three times a week through September, a free tennis social called Volleys & Vibes filled the courts at Crocker Amazon in the Excelsior, with Sunday sessions at Lowell High School. It is in its sixth season. It listed 13 sessions in the month, each listed under one player as that day’s host. Twelve were full before anyone walked on court.

Across San Francisco, 292 of 1,403 public gatherings showed full on the last read before doors in September. That is one in five, and it is the baseline every host is up against. The rooms that beat it had habits in common, and none of the habits needs a sponsor. These are the five that held up.

A second host. Events that listed two or more hosts filled 25 percent of the time: 219 of 867. Events with one host filled 14 percent of the time: 71 of 523. The typical co-hosted list ran to 35 names, against 14. The gap held in every week of the month. It also held for events with nothing to do with AI, where co-hosted rooms filled 24 percent of the time and solo rooms 13. A co-host brings a second address book. The count cannot separate that from anything else a partner adds, and a host may not need it to.

Two to four weeks of notice. Events that first appeared two to four weeks before doors filled 27 percent of the time, 52 of 193. Events that appeared less than a week out filled 16 percent, 78 of 480. Past four weeks there were too few to read, 14.

A subject. Book clubs and reading nights filled best, 34 percent. Titles that named no format filled at 15. The Love Potion Library, a bookshop and tearoom in Duboce Triangle, ran 16 nights in September. They included book clubs, a Jane Austen reader’s theater, a bedazzling workshop and a sound bath with silent reading. Seven were full before doors.

A price, if the night is worth one. Paid events filled 22 percent of the time, 40 of 185, and free ones 21 percent. The typical paid ticket was $25. Big Brain Bay Area ran ten talks at $27 a seat in bars, a winery, a theater and a hall across San Francisco, Oakland and Berkeley. Six were full before doors, among them a UC Berkeley psychologist on why people are so bad at being happy, with 256 signed up.

The empty night. Monday had the fewest listings, 96, and the best fill rate of any day, 25 percent, by a hair. Wednesday had more than three times the listings and filled at 24. Friday filled at 17.

Two more habits went with full rooms, though they may be symptoms more than causes. Events that asked guests for approval filled 26 percent of the time, against 15 for open doors. Events that hid the address until sign-up filled 25 percent, against 18. A host who expects a crowd is the one who turns approval on.

Confidence is medium on each habit. These are patterns across one month in one city, not experiments, and “full” means a host-set limit was reached, whatever that limit was. Sign-ups are not attendance. The co-host gap is the largest and the most consistent, and it is the one this desk would bet on.

Most of the month was meetups. These were the nights that were about something else, in date order, with the numbers each one posted.

BY THE DESK

The Corgi Cup. A remote-control car racing tournament at Corgi Cafe, thrown by Arize AI, a company whose product watches AI systems for repeat failures. The races were the metaphor. 344 signed up by the morning of the event. Wednesday, September 9 · Union Square · free · lu.ma/the-corgi-cup

ACROSS 跨. Now Place, a space in Chinatown, marked a year since it reopened with its first open-call show of risograph prints, by more than 40 artists. 150 signed up by the morning of the opening. Friday, September 11 · Chinatown · free · lu.ma/wpptamct

Why Are We So Bad at Being Happy? Dr. Iris Mauss, a psychology professor at UC Berkeley, on the gap between wanting happiness and getting it, in the Swedish American Hall. 256 signed up and the house was full. Thursday, September 17 · Duboce Triangle · $27 · lu.ma/4ge5bar2

7Pacific SF Bakery Run. Eight miles from Golden Gate Park to Dogpatch, with a pastry collected at Arsicault, Parachute and Breadbelly along the way. 64 signed up, full. Saturday, September 19 · starts at Bunny Meadow · $20 · lu.ma/4nkiwp04

Coffee & Tarot. A Brazilian coffee pop-up, a tarot reader and massages at The Love Potion Library. It had 22 names on September 2 and 326 by the morning of the event. Sunday, September 20 · Duboce Triangle · free · lu.ma/z4liunka

Banya & Beats. Alchemy Springs’ annual post-Burning Man party, with DJs, sauna sessions and a first look at its new bathhouse, capped at 40. Sunday, September 20 · Lower Nob Hill · lu.ma/r2t103f1

Mahjong Under the Moon. Now Place again, for the Mid-Autumn Festival: a blind tasting of mooncakes from different Chinatown bakeries, with a “Mooncake Passport” for notes, then mahjong. Full. Friday, September 25 · Chinatown · $25 · lu.ma/nowplace-87m2

Century of Coltrane. The Legroom Jazz Quartet and two guests played for John Coltrane’s 100th birthday. Its 45 tickets were gone before doors, and the page offered a livestream instead. Saturday, September 26 · Clarion Performing Arts Center, Chinatown · lu.ma/1fa249h3

Showerhacks. A 12-hour hackathon for “absurdly creative” ideas with “no economic viability needed.” First prize: $1,000 and a shower. 464 signed up. Saturday, September 26 · Rincon Hill · free · lu.ma/99857qk9

Hugg Magazine, Issue 003. A launch party and fashion show for an issue titled “This is What Our Friends Are Wearing.” It had 16 names on August 27 and 140 by the morning of the show. Saturday, September 26 · SoMa · $12 · lu.ma/jjmtr7ne

COCOON. The Magik*Magik Orchestra, marking 18 years, played around an audience lying on camping cots arranged in a cocoon. The listing called it the city’s first orchestra sleepover. Sold out before doors. Saturday, September 26, 9:30 p.m. · Gray Area, Mission · lu.ma/Magik18

An Architectural Tour of North Beach. Hard Reset, a group that takes people who work at screens out walking, sent the guide Katherine Petrin to explain Romeo flats, clinker brick and why Columbus Avenue cuts across the grid. 18 signed up, full. Sunday, September 27 · North Beach · $15 · lu.ma/5dk7rv41

SOURCES & RECEIPTS

1. The Frisconian’s count of public event listings on Luma with a venue in San Francisco and a start date from September 1 through September 30, 2026, Pacific time: 1,403 after removing 16 duplicate pages (Oakland 141, Berkeley 121, not counted here). Read nightly from public event pages; dump pulled October 11, 2026. “AI in the title” means the title contains AI, agent, agentic, LLM, GPT, MCP, model, machine learning, inference, robotics, Codex, Claude, OpenAI, Anthropic, Nvidia or a similar term; 308 listings. Sign-ups: the guest count at the last nightly read before doors, on the 826 San Francisco listings that show one; 53,352 in all, 21,410 at AI-titled events; medians 73 and 19. “Full”: the listing showed sold out at that same read; 83 of 308 AI-titled, 209 of 1,095 others. By week (Sept. 1–7, 8–14, 15–21, 22–30), AI share 16.0%, 20.9%, 20.3%, 26.4%. Reading and book-club titles: 11 of 32 full. 2. Listings lu.ma/prohibition-dreamforce (744, full) and lu.ma/barbarossa (709). Barbarossa Lounge, Instagram: “After nearly 11 unforgettable years, Barbarossa Lounge will close its doors at 714 Montgomery Street, with our final night on September 26, 2026,” read October 11, 2026. Dreamforce: September 15–17, 2026, Moscone Center, per salesforce.com/dreamforce/register. 3. lu.ma/thoughtexperiments (1,787) and lu.ma/shortstories (1,083): “most of these are carried over from previous events in this series. We don’t expect much more than 30 to attend.” Queries in receipts.json.

2. Same count as note 1, 1,403 San Francisco listings, September 2026. Full before doors: sold out at the last nightly read before the start time; 292 of 1,403. Hosts as listed on each page: two or more, 219 of 867 full (median list 35); one, 71 of 523 (median 14); 13 pages list none. By week, one host vs. two or more: 9 of 91 vs. 42 of 122; 18 of 121 vs. 50 of 203; 24 of 140 vs. 55 of 218; 20 of 171 vs. 72 of 324. Without AI in the title: 58 of 455 vs. 150 of 630. Notice: days from the listing’s first appearance in the nightly read to the event, listings first seen August 28 or later; under 7 days 78 of 480, 7–13 days 55 of 315, 14–27 days 52 of 193, 28 or more 1 of 14. Paid 40 of 185, free 252 of 1,218; median price $25 across 154 paid listings that show one. Monday 24 of 96, Wednesday 79 of 324, Friday 26 of 149. Approval required 196 of 760, not 96 of 643. Address hidden 142 of 558, shown 150 of 845. Reading and book clubs 11 of 32; no format named 74 of 481. Volleys & Vibes and Tempo sessions hosted under Prince Boucher’s calendar, 12 of 13 full. The Love Potion Library, 7 of 16. 5. Big Brain Bay Area, ten listings, September 2 to 24, 2026, all $27; 6 full before doors. “Why Are We So Bad at Being Happy?” with Dr. Iris Mauss, Swedish American Hall, September 17, lu.ma/4ge5bar2, 256 signed up, full. Queries in receipts.json.

3. Each listing’s public Luma page as read nightly, sign-ups and “full” at the last read before doors; descriptions paraphrased from the organizers’ own pages, and claims such as “first” are theirs. Queries in receipts.json.

The Frisconian · Published from forty-nine square miles surrounded by reality · thefrisconian.com · @deaconsanti