How does a product launch differ depending on the size of the company?

It depends on your resources and the skills of your team. 

A larger company might be able to tap into more channels successfully or might already have more users and so the launch will inherently be more amplified. 

You can still do a successful launch as a small company with some creativity and good storytelling! Try to think about the channels that will have the most impact given your constraints and work with a good designer to make compelling assets, and use Loom to create fun demos...(shameless plug!). 

I've worked at Series B startups all the way up to F500 companies.

The theory behind product launches is the same - you want to align your launch to business goals. But, the HOW (the tactics and resources) and the WHO (the team) behind executing a product launch are really where there are differences. 

At a F500 company, you've got dedicated teams for naming, brand, sales enablement, web, social, and more. PMMs might focus only on launch messaging at a larger company, and spend a lot of time on stakeholder management and alignment. At a smaller company, you've got fewer stakeholders to get in a room, so you can move very quickly, but PMMs will often end up wearing those hats worn by other teams (e.g. writing email copy, landing page copy, thinking about naming and branding, etc.)

You can read my answer about taking a Tiered approach in one of the other answers. If you're a lean start up, I would suggest focusing on doing just 2 Tier 1 launches a year, and sprinkle in two Tier 2s throughout the year (rather than the 3 Tier 1s 3 Tier 2s I recommend for a more mature company).

In addition to quanity of launches, you can use your "Bill of Deliverables" as a lever. Bill of Deliverables are the assets you are going to create for launch - think customers facing slides, messaging & positioning, one pagers, ads, landing pages, email campaigns, enablement training, press release, blog post, customer messaging etc). Instead of doing all of these, maybe you focus in on the 6 promotional activities that are going to drive the most momentum, awareness and pipeline for your business. 

You can also lean on others to help you. Empower your launch team members to use the messaging and positioning that you have created to do their work. For example, your head of SDR can write the prospecting scripts, your head of demand gen can write the email campaigns, etc and you can take the role of reviewing and editing. If you have budget to outsource anything, you can leverage great copy writing to write the blog post, think of witty ad blurbs etc. 

It looks like Loom has ~250 employees (according to LinkedIn), raised a total of $203.6M in their series C in 2021 (according to Crunchbase), and was valued at $1.53B. I’m sharing this mainly for context for other readers, even though my answer to your question will be a bit indirect because the startups I joined early were at least Series B and well-funded (i.e., not super early stage or lean).

The big differences between lean/small/early stage startups and bigger ones are:

• Budget—money will be tighter if there’s less funding. Teams need to be scrappier and do more growth hacking.

• Resources—you probably don’t have a team for every specialized function, and you may not even have a person for it (i.e., a copywriter, a social media manager). This means you will be wearing more hats. I joined Brex just before they announced their series C raise, when they were valued at $1B and had 175 employees, and we were still many months away from hiring a dedicated copywriter and social media manager. Fast forward to a series D raise, a $12.3B valuation, and 1,400 employees, and there are now entire dedicated teams and/or supporting agencies for these functions. In the early days, I was asked to design the art for some billboards in Figma; that stopped once we hired an in-house designer.

• Process—the younger the company, the fewer people, the less process. 

Communication—I stressed the importance of overcommunication in the previous answer. At a much smaller company, communicating is easier because everyone knows what everyone else is working on. If you can all fit in one room or on one video call, you probably don’t need to worry about certain teams missing context.

A successful product launch requires collaboration, coordination, and communication. A launch is easily the most cross-functional initiative a company takes on. It's a coordinated dance of different functional areas with distinct workflows working toward a common outcome.

Smaller companies are less complex and have fewer products. The 3Cs are easier. Bigger companies have more products and are more complex. The 3Cs are harder.

There is a need for much greater process rigor as a company grows. The swimlanes get narrower, and the number of stakeholders increases. Processes, frameworks, methods, and tools really make a difference. Heroics no longer win the day because heroics don't scale.