A study published in December 2001 by the ACM SIGGROUP Bulletin highlighted the lack of research on tools for blue-collar workers to find work in the digital age, expressing concerns about technology design choices potentially favoring managers over workers.

LinkedIn was established in December 2002.

LinkedIn, a business-oriented social network, was officially launched on May 5, 2003. It has since grown into a massively successful public company with over 800 million members.

In August 2004, LinkedIn reached 1 million users.

The 'Groups' feature was introduced to LinkedIn in July 2005.

In August 2005, LinkedIn implemented business accounts.

In March 2006, LinkedIn achieved its first month of profitability, marking a significant milestone in its growth.

By April 2007, LinkedIn had reached 10 million users.

The 'Profile views' feature was released in May 2007.

In February 2008, a mobile version of the site was launched in six languages including Chinese, English, French, German, Japanese, and Spanish.

In 2009, Syrian users reported that LinkedIn server stopped accepting connections originating from IP addresses assigned to Syria due to US export and re-export control laws. LinkedIn prohibited member accounts or access from Cuba, Iran, North Korea, Russia, Sudan, or Syria.

In 2010, LinkedIn hit a huge growth milestone with 90 million members and 1,000 users, opening an International Headquarters in Dublin, Ireland.

On May 19, 2011, shares of LinkedIn rose as much as 171% on their first day of trade on the New York Stock Exchange and closed at $94.25, more than 109% above IPO price.

In June 2012, approximately 6.4 million LinkedIn user passwords were stolen by hackers, leading to the publication of stolen hashes online. LinkedIn responded by asking users to change their passwords and later added two-factor authentication for enhanced security.

In July 2012, LinkedIn acquired 15 key Digg patents for $4 million, including a patent related to voting up stories with a button click.

In October 2012, LinkedIn introduced the LinkedIn Influencers program, showcasing global thought leaders sharing professional insights with members.

In January 2013, LinkedIn dropped support for LinkedIn Answers, citing a focus on developing new ways to share and discuss professional topics.

In June 2013, CardMunch was integrated as an available LinkedIn app.

In October 2013, LinkedIn announced 'Intro', a service for iPhone users that inserts a thumbnail of a person's LinkedIn profile in correspondence with that person when reading mail messages in the native iOS Mail program.

In November 2013, LinkedIn announced the addition of Showcase Pages to the platform.

In February 2014, LinkedIn launched its Simplified Chinese language version named '领英' (Lǐngyīng; lit. 'leading elite'), extending their service in China. CEO Jeff Weiner acknowledged the need to censor content to comply with Chinese rules.

In April 2014, LinkedIn announced that it had leased 222 Second Street in San Francisco to accommodate up to 2,500 employees. The goal was to bring sales, marketing, and research teams together.

As of 2015, LinkedIn had more than 400 million members in over 200 countries and territories, making it a significant player in the professional networking space.

The deal between Microsoft and LinkedIn was completed on December 8, 2016. Microsoft allowed LinkedIn to retain its brand and independence, with the CEO reporting to Microsoft's CEO.

As of April 2017, LinkedIn had over 500 million members worldwide, continuing to innovate and enhance user experience.

An analysis published in May 2017 by Research Policy revealed that PhD holders moving into industry were more likely to have LinkedIn accounts and larger networks, especially if they had co-authors abroad or had moved abroad after obtaining their PhD.

According to the company's website, LinkedIn Referrals was no longer available after May 2018.

In July 2018, Credit Wise reported 'dark web' email and password exposures from LinkedIn, leading to extortion emails being sent to users. LinkedIn linked this incident to the 2012 breach, although evidence was lacking.

An empirical analysis conducted by Foster School of Business professors Melissa Rhee, Elina Hwang, and Yong Tan in October 2018 revealed that creating LinkedIn connections with professionals in a target company or field did not significantly help job seekers in obtaining referrals due to job similarity and self-protection from competition.

Qualitative interviews conducted by sociologists in July 2019 with human resources recruiters in the Southern United States showed that recruiters targeted passive candidates on LinkedIn for high-skilled positions, leading to a bifurcated job market where employed high-skilled workers are poached while active job seekers face hyper-competition on online job boards.

A working paper in September 2019 by economists and scholars in South Africa found that training job seekers to use LinkedIn as part of job readiness programs increased employment by 10% by reducing information frictions between job seekers and employers, although it did not reduce job search costs.

In May 2020, LinkedIn launched 'LinkedIn Events' to help organizations connect safely in real-time, providing a platform for networking and collaboration.

In June 2020, Jeff Weiner transitioned from the CEO role at LinkedIn to become the executive chairman, with Ryan Roslansky taking over as the new CEO.

In late July 2020, LinkedIn announced the layoff of 960 employees, approximately 6% of its workforce, citing the effects of the global COVID-19 pandemic as the reason.

A breach disclosed in April 2021 affected 500 million LinkedIn users, exposing their information. LinkedIn attributed the data aggregation to web scraping from various sites.

In June 2021, a breach was reported to have affected 92% of LinkedIn users, exposing contact and employment information. LinkedIn clarified that only publicly listed information was included in the breach.

In July 2021, LinkedIn was blocked in Kazakhstan, adding to the list of countries where the platform faced restrictions. The reasons for the block were not explicitly mentioned.

In September 2021, LinkedIn discontinued the LinkedIn Stories feature that was rolled out worldwide in October 2020.

In October 2021, Microsoft confirmed that LinkedIn would be shutting down in China and replaced with InJobs, a China exclusive app. This decision was made due to difficulties in operating environments and increasing compliance requirements.

In 2022, LinkedIn was ranked first in a list of brands most likely to be imitated in phishing attempts, highlighting the platform's susceptibility to such attacks.

In May 2023, LinkedIn announced that it would be phasing out the app by 9 August 2023. The reasons behind this decision were not explicitly mentioned in the provided text.

In August 2023, several LinkedIn users were targeted by hackers in a hijacking and phishing bid, resulting in threats of account deletion if ransom was not paid.

At LinkedIn's Talent Connect summit in October 2023, the company announced new HR-specific tools, including a generative AI update to its Recruiter service.

On March 6, 2024, LinkedIn launched new features to help HR better connect with employees about internal opportunities and design upskilling programs.