# Jonathan Siegel

> Jonathan Siegel is a seed investor at Bass & Siegel (San Francisco) backing Software and SaaS. See 18 investments, check sizes, portfolio. Updated Aug 2026.

- Type: Angel Investor
- Fund: [Bass & Siegel](https://shizune.co/investors/profile/bass-siegel)
- Location: San Francisco, United States
- Total investments: 18
- Last investment: Sep 2024
- Lead investor: 0%
- Last updated: Aug 2026
- LinkedIn: http://www.linkedin.com/in/jsiegel
- X (Twitter): http://twitter.com/usiegj00
- Website: http://www.jsiegel.com
- Facebook: http://www.facebook.com/drsiegel

Jonathan Siegel is a seed investor at Bass & Siegel in San Francisco focused on Software and SaaS. Jonathan Siegel is the Partner of Bass and Siegel. He previously worked at Earth Class Mail as a Chairman. Jonathan Siegel attended Brown University.

## Round sizes

| Stage | Round size |
| --- | --- |
| Seed | $200k–$3.5M |
| Pre-Seed | $700k–$1.1M |

## Investment focus

### Industry

| Industry | Investments | Share |
| --- | --- | --- |
| Software | 6 | 33% |
| SaaS | 5 | 28% |
| Information Technology | 5 | 28% |
| Apps | 3 | 17% |
| Enterprise Software | 3 | 17% |

46 industries tracked in total.

### Stage

| Stage | Investments | Share |
| --- | --- | --- |
| Seed | 12 | 67% |
| Pre-Seed | 3 | 17% |
| Angel | 1 | 6% |
| Series A | 1 | 6% |
| Series B | 1 | 6% |

### Country

| Country | Investments | Share |
| --- | --- | --- |
| United States | 14 | 78% |
| Japan | 1 | 6% |
| Poland | 1 | 6% |
| United Kingdom | 1 | 6% |

## Investments

| Company | Description | Amount | Stage | Date | Website |
| --- | --- | --- | --- | --- | --- |
| Arcjet | Arcjet helps developers protect their apps in just a few lines of code. Implement rate limiting, bot protection, email validation, and defense against common attacks. | $3.6M | Seed | Sep 10, 2024 |  |
| Sixty AI | Sixty is the next generation social graph. Its AI-powered personal assistant expands the power of your network and handles the tedious but essential daily grind that can overwhelm your inbox, meetings, networking and sense of well-being. Sixty helps you spend less time at the keyboard and more time connecting with humans. | $3M | Seed | Jun 27, 2023 |  |
| PilotGo | PilotGo is a digital assistant for car workshops that handles what nobody likes: phone calls, notes, orders, and quotes. It learns from every conversation, order, and repair to automate repetitive tasks — so staff can focus on fixing cars, helping customers, and growing the business. - Phone calls and scheduling - Quoting and parts ordering -Repair management - Client relationship management | $932K | Seed | Sep 22, 2022 |  |
| PilotGo | PilotGo is a digital assistant for car workshops that handles what nobody likes: phone calls, notes, orders, and quotes. It learns from every conversation, order, and repair to automate repetitive tasks — so staff can focus on fixing cars, helping customers, and growing the business. - Phone calls and scheduling - Quoting and parts ordering -Repair management - Client relationship management | $1M | Pre-Seed | Sep 22, 2022 |  |
| SignTime | Sign Time works on creating and running electronic contract services. They provide more than simply electronic contracts with their e-signatures. Order forms, waivers, contracts, employment agreements any approval that clients need to maintain on file can be signed with them. SignTime e-signature services go beyond electronic contracts. SignTimecan sign any approval that is needed to keep on file, such as order forms, waivers, contracts, and employment agreements. | $2.7M | Series B | Sep 20, 2022 |  |
| Arro | Build better products using AI-powered research | $1.1M | Pre-Seed | Jan 13, 2022 |  |
| Autify | Autify is an AI-focused company that offers software testing solutions to address the challenges associated with automation testing. The company's flagship product, Autify No Code, empowers anyone to create automated end-to-end tests for their applications. Additionally, Autify's new product, Zenes, aims to simplify the process ofcreating new software tests through AI, allowing customers to work directly with the company's AI agent to generate tests from product documents. | $10M | Series A | Oct 06, 2021 |  |
| Anzen | Anzen is a management insurance and operations tool using real-time HRIS and SaaS integrations to identify and avoid management risks. The company was founded in 2020 and is headquartered in San Francisco, California, United States. | $700K | Pre-Seed | Jan 21, 2021 |  |
| Dark | Dark is holistic programming language, editor, and hosted infrastructure. | $3.5M | Seed | Jul 15, 2017 |  |
| Coast Technologies | Startup based in Pleasanton, CA in stealth mode. |  | Seed | Mar 29, 2016 |  |

10 of 18 investments shown.

## Co-investors
- [ff Venture Capital](https://shizune.co/investors/profile/ff-venture-capital) — VC Fund, 2 deals together
- [Movens Capital](https://shizune.co/investors/profile/movens-capital) — VC Fund, 2 deals together
- [Presto Ventures](https://shizune.co/investors/profile/presto-ventures) — VC Fund, 2 deals together
- [RKKVC](https://shizune.co/investors/profile/rkkvc) — VC Fund, 2 deals together
- [Startup Wise Guys](https://shizune.co/investors/profile/startup-wise-guys) — VC Fund, 2 deals together
- [Script Capital](https://shizune.co/investors/profile/122-west-ventures) — VC Fund, 1 deal together

## About Bass & Siegel

VC Fund · Irvine, United States

Bass & Siegel offer strategic representation at the nexus of startup, venture capital, and tech.

1 contacts available at Bass & Siegel.

| Name | Title | Profile |
| --- | --- | --- |
| Jonathan Siegel | Partner | https://shizune.co/investors/profile/jonathan-siegel |

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## FAQ

### What does Jonathan Siegel invest in?

Jonathan Siegel invests primarily in Software, SaaS and Information Technology startups, most often at Seed and Pre-Seed stage. Most of the 18 investments tracked by Shizune back companies in United States. The Investment Focus section breaks down every industry, stage and country in the portfolio.

### What is Jonathan Siegel's check size?

Jonathan Siegel typically joins rounds of $200k–$3.5M at Seed and $700k–$1.1M at Pre-Seed. These ranges are 10th–90th percentile round sizes calculated from confirmed public funding rounds, so they are a realistic guide to the rounds Jonathan Siegel participates in.

### When did Jonathan Siegel last invest?

The most recent investment recorded for Jonathan Siegel closed in Sep 2024. Shizune tracks 18 investments in total for this profile, including round sizes, stages and portfolio companies, all sourced from confirmed public funding rounds and refreshed monthly.

### Is Shizune's investor data accurate?

Yes — every stat on this profile is calculated from confirmed public funding rounds monitored across hundreds of sources since 2020. This profile was last refreshed in Aug 2026 and is updated monthly. Spotted something off? Use the “Suggest an edit” link near the top of the page.

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