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Portfolio construction, reserves and diversification

A small number of successful investments may account for much of an angel portfolio’s return. Plan how many companies to back, how much to keep for later rounds and how to spread investments over several years, and test those choices against research on angel returns.
Foundation7 min readLast reviewed 2 September, 2026

The portfolio is the unit

Published angel-returns data consistently shows that a few large successes account for most returns. In the 2007 US study of 1,137 exits, 52 per cent returned less than the capital invested; 7 per cent returned more than 10x and produced 75 per cent of all dollar returns.

The 2009 UK study found the same shape, with 56 per cent below capital and 9 per cent of exits producing close to 80 per cent of positive cash flows.

For a business angel (forretningsengel) the return on the book is decided almost entirely by whether an outlier is in it. Holding four or five positions is a bet that you picked the one in ten or fourteen without being able to tell in advance which it is.

A balanced portfolio reduces the risk of losing everything and caps what a single spectacular position can do to your total return. You are buying a better median at the cost of the extreme upside.

How many positions

The evidence points to more positions than most angels hold, and the gap between the simulation and the practitioner floor is where you set your own target.

StudyWhat it says
Gregson, Bock and Harrison, 2017 — simulation across the angel-returns datasetsSmaller portfolios show a higher mean but a dramatically lower median; portfolios above 50 investments are required to significantly reduce the risk of poor returns
Seraf practitioner guidance (Lord and Mirabile)10 investments is the absolute minimum; 20 is better than 10, and 50 is better than 20
UK angel market survey, 2020UK angels had made a mean of 17.1 investments over their investing lifetime

Fifty is more than one person can attend to, and attention shows up in the returns. The same 2007 study found that angels engaging with a company once or twice a month saw 3.7x, against 1.3x for those engaging once or twice a year, and that investments inside the angel’s own industry expertise returned roughly twice as much.

These correlations suggest that engagement matters. To maintain a broad portfolio while staying useful to companies, share the work. Invest alongside others, let a lead run the diligence and take the board seat on each case, and keep your own deep engagement for the companies where your experience is useful.

  • Starting out: set ten as the target, and reach it by co-investing, with smaller investments, before making larger investments alone.
  • With capital for more: the evidence says take twenty or more.
  • With a sector focus: spend your engagement on the companies inside it, where the data says it pays, and follow a lead on the rest.
  • In a syndicate: shared diligence is what lets each member reach the count without doing the work ten times.

Reserves: the next round is coming

A growing company may need another round; one that becomes self-financing may not. Plan for the funding needs and dilution scenarios when making the first investment.

Named practitioner guidance puts the initial investment at 25 to 50 per cent of what you intend to commit to a company in total, which means holding one to three times the first investment in reserve. No study prescribes a ratio; it is a rule of thumb from experienced angels.

Without reserves, you may face dilution (utvanning) just as the company begins to succeed and you want to invest again.

In UK activity data, the mean follow-on investment was GBP 77,000 against a mean initial investment of GBP 108,000, with medians of GBP 25,000 and GBP 45,000. A follow-on investment, when it comes, is half to three quarters of the first one.

NorBAN publishes the same picture for Norway. Only about a third of the angels in its network indicate capacity to follow on in a later round, and most tickets sit between 0.5 and 2 MNOK, with round-filling tickets around 100,000 kroner and the larger ones around 1 million.

Those are network-wide figures, not a forecast of your cap table. Ask each investor about follow-on capacity. Decide whether to reserve capital yourself or plan to accept dilution.

Follow-on money has historically underperformed. In the 2007 US data, 29 per cent of exited investments had received follow-on from the angel, and those exits returned 1.4x against 3.6x for exits without follow-on; the 2009 UK study found follow-on exits at 1.2x.

Keep reserves for companies that are making progress. Funding a failing company adds to your exposure and leaves less for stronger investments.

Write a short reserve policy before your first investment, so you have criteria in place when a founder asks for more money.

  1. Decide the total you are prepared to put into one company.
  2. Make the first investment 25 to 50 per cent of that total, and earmark the rest.
  3. Release the reserve only on evidence that the company is working, and let the earmark lapse where it is not.
  4. Decide now, and say so, whether you can follow at all.

Pacing across years

Entry prices move with the funding cycle. A portfolio assembled in eighteen months is priced by one market, and if that market was expensive, every position in the book carries the same problem.

Deploying the same capital over four or five years gets you several price environments. It is the only vintage diversification available to an investor who cannot time the cycle.

Pacing also disciplines selection. If your plan is four investments a year, a year with two cases worth backing produces two investments, because deal flow quality sets the pace.

Whether the shares sit with you personally or in a holding company changes how much of an exit is available to redeploy, because a realised gain is taxed differently in the two (Skatteetaten). For pacing, work from the after-tax proceeds.

The axes that actually diversify

A portfolio with many companies can still be concentrated. Check stage, vintage, sector and geography as well as the number of positions.

AxisWhat it protects against, and the rule
CountToo few tickets for the outlier to be in the book. Ten positions is a floor, not a target.
StageOne financing environment deciding whether the whole book gets funded. Mix seed (såkorn) entries with later, better-evidenced rounds.
VintageOne valuation season setting every entry price. Spread deployment over at least three to five years.
SectorA single technology, regulation or customer budget deciding every outcome. Cap the share of capital committed to any one theme.
GeographyOne national exit market and one public-funding regime. Take exposure outside Norway deliberately, and only where you can still follow the company.

Adding more companies within the same theme gives limited diversification. Fifteen positions in Nordic business software, all bought at seed within two years, is one bet expressed fifteen times. Ask of each new case what it is not correlated with in the rest of your book.

Named practitioner guidance puts 5 to 10 per cent of investable net worth into the asset class. The UK regulator draws a comparable retail line, requiring self-certified restricted investors to confirm they will not put more than 10 per cent of net assets into high-risk investments; no Norwegian regulator publishes an equivalent figure.

Both assume the financial foundation is already in place, with emergency reserves, housing and pension before angel capital. The allocation, divided by the position count and net of reserves, is the size of your first investment, so work it out before the first case arrives.

Keeping the book visible

Portfolio decisions get made on memory unless someone writes the numbers down. The minimum record is one row per company.

  • Amount invested and date, and the instrument.
  • Current ownership percentage and the price of the last round.
  • The reserve earmarked for that company.
  • The date of the last substantive contact.

Use the sheet to answer the questions that guide your next investment. Update it at every round and every contact, and read it before every new case.

  • How many positions are actually held.
  • How much of the planned allocation is already committed.
  • Which reserve is spoken for and which is free.
  • How much of the book was bought in the same year, at the same stage, in the same theme.

Key takeaways

  • A simulation study of the angel-returns datasets found that portfolios above 50 investments are needed to significantly reduce the risk of a poor outcome; practitioner guidance treats 10 as the absolute floor.
  • Reserve one to three times your first investment for follow-on rounds, so the initial investment is 25 to 50 per cent of what you plan to put into that company.
  • Follow-on money has historically underperformed. In Wiltbank and Boeker's 2007 US study, exits that received follow-on returned 1.4x against 3.6x for those that did not.
  • Deploying across several years diversifies entry prices. A book bought in one season is priced by one market, and if that market was expensive every position carries the same problem.
  • Named practitioner guidance puts 5 to 10 per cent of investable net worth in the asset class, once emergency reserves, housing and pension are in place.

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