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The GLG (Gerson Lehrman Group) expert network was founded in 1998 and is today the world’s largest expert network. In October 2022, GLG had 2,300+ employees with offices in 13 countries. Its expert network database contained more than 1 million unique experts with hundreds more being recruited every day.

Looking to use an expert network like GLG? Use these resources:

  1. Guide to getting started with expert networks.

  2. Compare GLG to other expert networks.

The history of GLG

GLG remains a large vendor to many clients and holds a significant market share. However, GLG's recent growth has been slower, and it has been losing market share to new entrants. Many firms have moved away from only using GLG, to also using e.g. Alphasights, Dialectica, Third Bridge, or multi-network access through Inex One.

When GLG started, experts were recruited “offline”, at fairs and events, as recounted by a senior expert. Their expert network was "a decent phone directory", quite far from today’s browsable database. With the evolution of the expert network industry, even this database has lost some of its importance:

Visualization of the size of the LinkedIn and GLG databases

Comparison of LinkedIn with GLG's database

To continue growing, the firm has explored different business areas over the years. These include:

  • The 2008 collaboration with Credit Suisse. GLG offered access to the bank’s analysts, but this was later shut down.

  • The 2010 partnership with Bloomberg, later shut down.

  • The 2011 Q&A website Gplus/GLG High table, shut down in 2013.

  • The 2014 GLG Share, offering expert calls for entrepreneurs. No longer active.

  • The 2016 GLG Law, offering expert witness services (experts are brought in on litigation cases). Still active.

  • Current GLG service offering also includes expert surveys, GLG Events (conferences, roundtables and workshops with GLG’s most desired experts), GLG Library (a database of teleconference transcripts available to subscribers), GLG Projects (providing experts for longer-term assignments such as due diligence studies) and GLG Placements (providing c-suite professionals to join the client's team for a longer time period).

  • In May 2022, GLG began offering its GLG Library content on Sentieo, a data platform. Sentio had recently been acquired by Alphasense, which offers the library Alphasense Stream. GLG agreeing to aggregation is a big deal, and could set a precedent for aggregating also its calls business.

The 1h expert phone call has remained GLG's core business, throughout the years of service iterations.

Milestones and important events for GLG:

“GLG cubs” – expert networks started by former employees

GLG public offering (IPO) in 2021

On 18 October 2021, GLG filed an S-1 with the US Securities and Exchange Commission, to go public on Nasdaq under the ticker "GLGX". The process was jointly led by Morgan Stanley and Goldman Sachs. However, the IPO was rumored to be halting, and in late March 2022 finally withdrawn.

The filing process revealed data on revenue and margins that were previously not known to the public (however our expert network market sizing was pretty close!).

Had it gone public, GLG would have followed VisasQ, which listed on the Tokyo stock exchange in March 2020. In the summer of 2021, Capvision filed early documents ahead of a future IPO in Hong Kong.

Further reading

GLG has evolved significantly over time. We discuss the emergence and history of GLG in our history of the expert network industry. Furthermore, a senior expert shared colorful insights on the expert network’s evolution in this piece. In 2019, GLG generated close to $550m revenues and remains the largest expert network in the industry by revenue.

GLG Strategic Solutions / GLG Strategic Projects is the company's consulting arm. It is led by a former McKinsey consultant and is promoted as a full-blown consulting service. From the GLG Projects website in September 2020 (our highlighting):

"GLG Projects deliver strategic recommendations informed by real-world expertise. For each engagement, we put together tailored teams of top-tier consultants and subject-matter experts with experience across industries and disciplines. Our work includes fully managed

  • market assessments,

  • due diligence studies,

  • brand analyses,

  • voice-of-customer studies, and

  • corporate strategy projects."

Some of GLG's significant consulting clients have shown concern about GLG effectively competing with them, while it also handles their sensitive consulting project data. As per September 2020, roughly 200 employees (~10% of GLG's workforce) were involved in the strategic projects branch.

Evolution of the GLG logo:


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